Science.gov

Sample records for aluminum chloride solution

  1. Effect of sulfate ions on corrosion inhibition of AA 7075 aluminum alloy in sodium chloride solutions

    SciTech Connect

    Wu, T.I.; Wu, J.K.

    1995-03-01

    The effect of the addition of sulfate ions on corrosion inhibition of Aluminum Association (AA) 7075 aluminum (Al) alloy (UNS A97075) in aqueous solution was studied. Corrosion behavior was affected significantly by the addition of SO{sub 4}{sup 2{minus}}. The corrosion morphology and corrosion rate changed with various thermomechanical treatment sand with the relative amount of sodium sulfate and sodium chloride in the immersion test solutions. However, the inhibitive effect of SO{sub 4}{sup 2{minus}} was evident with the increasing relative amount of Na{sub 2}SO{sub 4}. Corrosion data and morphologies obtained were illustrated by a competitive anion adsorption mechanism.

  2. An XAFS study of nickel chloride in the ionic liquid 1-ethyl-3-methyl imidazolium chloride/ aluminum chloride

    SciTech Connect

    D Roeper; G Cheek; K Pandya; W OGrady

    2011-12-31

    Nickel chloride was studied with cyclic voltammetry and X-ray absorption spectroscopy in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride (EMIC) ionic liquids. Acidic melts display metal stripping peaks which are not observed in the basic melt. EXAFS analysis shows that the nickel is tetrahedrally coordinated with chloride ions in the basic solution. In the acidic solution the nickel is coordinated by six chloride ions that are also associated with aluminum ions.

  3. Effects of applied potential on the stress corrosion cracking behavior of 7003 aluminum alloy in acid and alkaline chloride solutions

    NASA Astrophysics Data System (ADS)

    Zhang, Xiao-yan; Song, Ren-guo; Sun, Bin; Lu, Hai; Wang, Chao

    2016-07-01

    Potentiodynamic polarization tests and slow strain rate test (SSRT) in combination with fracture morphology observations were conducted to investigate the stress corrosion cracking (SCC) behavior of 7003 aluminum alloy (AA7003) in acid and alkaline chloride solutions under various applied potentials ( E a). The results show that AA7003 is to a certain extent susceptible to SCC via anodic dissolution (AD) at open-circuit potential (OCP) and is highly susceptible to hydrogen embrittlement (HE) at high negative E a in the solutions with pH levels of 4 and 11. The susceptibility increases with negative shift in the potential when E a is less than -1000 mV vs. SCE. However, the susceptibility distinctly decreases because of the inhibition of AD when E a is equal to -1000 mV vs. SCE. In addition, the SCC susceptibility of AA7003 in the acid chloride solution is higher than that in the alkaline solution at each potential. Moreover, the effect of hydrogen on SCC increases with increasing hydrogen ion concentration.

  4. FT-Raman spectroscopic analysis of the most probable structures in aluminum chloride and tetrahydrofuran solutions

    NASA Astrophysics Data System (ADS)

    Alves, Carolina C.; Campos, Thiago B. C.; Alves, Wagner A.

    2012-11-01

    A study by concentration-dependent Raman spectroscopy is presented for solutions of AlCl3 in THF. The formation of small amounts of AlCl4- has been evidenced by the appearance of only one band at 348 cm-1 in the most diluted salt solution. Another band at 330 cm-1 starts rising with increasing salt concentration and it seems to belong to the [AlCl3(THF)3] complex. Indeed, this octahedral entity was confirmed by the quantitative analysis performed at the band envelope at 915 cm-1. At this region, additional bands at 927 and 858 cm-1 were observed and assigned to the C-C and C-O stretching modes, respectively, of THF molecules coordinated to the aluminum salt. Besides them, another band at 1042 cm-1 clearly reveals the existence of this population of molecules. Although neutral octahedral complexes seem to be the major species in more concentrated salt solutions, the Raman spectra show the presence of complex ions in whole studied concentration range.

  5. FT-Raman spectroscopic analysis of the most probable structures in aluminum chloride and tetrahydrofuran solutions.

    PubMed

    Alves, Carolina C; Campos, Thiago B C; Alves, Wagner A

    2012-11-01

    A study by concentration-dependent Raman spectroscopy is presented for solutions of AlCl(3) in THF. The formation of small amounts of AlCl(4)(-) has been evidenced by the appearance of only one band at 348 cm(-1) in the most diluted salt solution. Another band at 330 cm(-1) starts rising with increasing salt concentration and it seems to belong to the [AlCl(3)(THF)(3)] complex. Indeed, this octahedral entity was confirmed by the quantitative analysis performed at the band envelope at 915 cm(-1). At this region, additional bands at 927 and 858 cm(-1) were observed and assigned to the C-C and C-O stretching modes, respectively, of THF molecules coordinated to the aluminum salt. Besides them, another band at 1042 cm(-1) clearly reveals the existence of this population of molecules. Although neutral octahedral complexes seem to be the major species in more concentrated salt solutions, the Raman spectra show the presence of complex ions in whole studied concentration range. PMID:22925986

  6. Corrosion behavior of aluminum-alumina composites in aerated 3.5 percent chloride solution

    NASA Astrophysics Data System (ADS)

    Acevedo Hurtado, Paul Omar

    Aluminum based metal matrix composites are finding many applications in engineering. Of these Al-Al2O3 composites appear to have promise in a number of defense applications because of their mechanical properties. However, their corrosion behavior remains suspect, especially in marine environments. While efforts are being made to improve the corrosion resistance of Al-Al2O3 composites, the mechanism of corrosion is not well known. In this study, the corrosion behavior of powder metallurgy processed Al-Cu alloy reinforced with 10, 15, 20 and 25 vol. % Al2O3 particles (XT 1129, XT 2009, XT 2048, XT 2031) was evaluated in aerated 3.5% NaCl solution using microstructural and electrochemical measurements. AA1100-O and AA2024T4 monolithic alloys were also studied for comparison purposes. The composites and unreinforced alloys were subjected to potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) testing. Addition of 25 vol. % Al2O 3 to the base alloys was found to increase its corrosion resistance considerably. Microstructural studies revealed the presence of intermetallic Al2Cu particles in these composites that appeared to play an important role in the observations. Pitting potential for these composites was near corrosion potential values, and repassivation potential was below the corresponding corrosion potential, indicating that these materials begin to corrode spontaneously as soon as they come in contact with the 3.5 % NaCl solution. EIS measurements indicate the occurrence of adsorption/diffusion phenomena at the interface of the composites which ultimately initiate localized or pitting corrosion. Polarization resistance values were extracted from the EIS data for all the materials tested. Electrically equivalent circuits are proposed to describe and substantiate the corrosive processes occurring in these Al-Al2O 3 composite materials.

  7. Production of anhydrous aluminum chloride composition

    DOEpatents

    Vandergrift, G.F. III; Krumpelt, M.; Horwitz, E.P.

    1981-10-08

    A process is described for producing an anhydrous aluminum chloride composition from a water-based aluminous material such as a slurry of aluminum hydroxide in a multistage extraction process in which the aluminum ion is first extracted into an organic liquid containing an acidic extractant and then extracted from the organic phase into an alkali metal chloride or chlorides to form a melt containing a mixture of chlorides of alkali metal and aluminum. In the process, the organic liquid may be recycled. In addition, the process advantageously includes an electrolysis cell for producing metallic aluminum and the alkali metal chloride or chlorides may be recycled for extraction of the aluminum from the organic phase.

  8. Fabrication and icing property of superhydrophilic and superhydrophobic aluminum surfaces derived from anodizing aluminum foil in a sodium chloride aqueous solution

    NASA Astrophysics Data System (ADS)

    Song, Meirong; Liu, Yuru; Cui, Shumin; Liu, Long; Yang, Min

    2013-10-01

    An aluminum foil with a rough surface was first prepared by anodic treatment in a neutral aqueous solution with the help of pitting corrosion of chlorides. First, the hydrophobic Al surface (contact angle around 79°) became superhydrophilic (contact angle smaller than 5°) after the anodizing process. Secondly, the superhydrophilic Al surface became superhydrophobic (contact angle larger than 150°) after being modified by oleic acid. Finally, the icing property of superhydrophilic, untreated, and superhydrophobic Al foils were investigated in a refrigerated cabinet at -12 °C. The mean total times to freeze a water droplet (6 μL) on the three foils were 17 s, 158 s and 1604 s, respectively. Thus, the superhydrophilic surface accelerates the icing process, while the superhydrophobic surface delays the process. The main reason for this transition might mainly result from the difference of the contact area of the water droplet with Al substrate: the increase in contact area with Al substrate will accelerate the heat conduct process, as well as the icing process; the decrease in contact area with Al substrate will delay the heat conduct process, as well as the icing process. Compared to the untreated Al foil, the contact area of the water droplet with the Al substrate was higher on superhydrophilic surface and smaller on the superhydrophobic surface, which led to the difference of the heat transfer time as well as the icing time.

  9. An XAFS Study of Tantalum Chloride in the Ionic Liquid 1-ethyl-3-methyl Imidazolium Chloride/ aluminum Chloride

    SciTech Connect

    D Roeper; K Pandya; G Cheek; W OGrady

    2011-12-31

    Tantalum chloride was studied with extended X-ray absorption fine structure spectroscopy (XAFS) in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride ionic liquids (ILs). Anhydrous Ta2Cl10 is more soluble in the basic solution than in the acidic solution and the X-ray absorption data shows that the coordination shell of chlorides around the tantalum is larger in the basic solution. In the acidic solution, tantalum has five chlorides in its coordination shell while in the basic solution; the tantalum is coordinated by seven chlorides. This indicates that the Lewis acidity of the tantalum chloride causes the Ta to coordinate differently in the acidic and the basic solutions.

  10. X-ray photoelectron spectroscopic study of the oxide film on an aluminum-tin alloy in 3.5% sodium chloride solution

    SciTech Connect

    Venugopal, A.; Selvam, P.; Raja, V.S.; Veluchamy, P.; Minoura, H.

    1997-10-01

    Oxide films on Al and an Al-Sn alloy were analyzed by x-ray photoelectron spectroscopy (XPS) after immersion in 3.5% sodium chloride (NaCl) solution. Results showed Sn exhibited both Sn{sup 2+} and Sn{sup 4+} oxidation stats in the oxide film. It was proposed that incorporation of these cations in the film would result in generation of more anionic and cationic vacancies in aluminum oxide (Al{sub 2}O{sub 3}), leading to active dissolution of Al.

  11. Aluminum: Reducing chloride emissions from aluminum production

    SciTech Connect

    Simon, P.

    1999-09-29

    Reynolds Metals Company (RMC), with assistance from a NICE{sup 3} grant, is developing for commercialization a closed-loop control process that greatly reduces chlorine emissions and increases plant efficiency while maintaining metal quality. The process still utilizes chlorine to remove impurities during aluminum processing, but is more effective than current methods. With the new technology chlorine in the stack is monitored and input chlorine is adjusted continuously. This optimization of chlorine use results in substantially less waste because less chlorine has to be bought or produced by aluminum manufacturers. This innovation is a significant improvement over conventional aluminum treatments, in which chlorine is injected in a more costly and wasteful manner. By the year 2010, the new technology has the potential to reduce the energy it takes to create chlorine by 8.4 billion Btu per year and to cut greenhouse gas emissions by 1,377 tons per year.

  12. Separation of platinum and rhodium from chloride solutions containing aluminum, magnesium and iron using solvent extraction and precipitation methods.

    PubMed

    Raju, B; Kumar, J Rajesh; Lee, Jin-Young; Kwonc, Hyuk-Sung; Kantam, M Lakshmi; Reddy, B Ramachandra

    2012-08-15

    The solvent extraction and precipitation methods have been used to develop a process to separate platinum and rhodium from a synthetic chloride solutions containing other associated metals such as (mg/L): Pt-364, Rh-62, Al-13880, Mg-6980, Fe-1308 at <1M HCl acidity. At pH 3.4, the quantitative precipitation of Al and Fe was achieved using 10 wt% Na(3)PO(4)·12H(2)O, with ~4% loss of Pt and Rh due to adsorption phenomenon. The selective separation of platinum was carried out with 0.01 M Aliquat 336 (a quaternary ammonium salt) at an aqueous to organic ratio (A/O) of 3.3 in two stages. Stripping of Pt from loaded organic (LO) at O/A ratio 6 with 0.5 M thiourea (tu) and HCl indicated that ~99.9% stripping efficiency. In stripping studies, needle like crystals of Pt were found and identified as tetrakis (thiourea) platinum (II) chloride ([Pt(tu)(4)]Cl(2)). The selective precipitation of rhodium was performed with (NH(4))(2)S from platinum free raffinate with a recovery of >99%. PMID:22664260

  13. A Green Alternative to Aluminum Chloride Alkylation of Xylene

    ERIC Educational Resources Information Center

    Sereda, Grigoriy A.; Rajpara, Vikul B.

    2007-01-01

    An acutely less toxic 2-bromobutane is used to develop a simple graphite-promoted procedure of alkylation of p-xylene. It is further demonstrated that aluminum chloride is not required, the need for aqueous workup is eliminated, waste solutions are not produced and the multiple use of the catalyst is allowed.

  14. Removal of trace mercury (II) from aqueous solution by in situ MnO(x) combined with poly-aluminum chloride.

    PubMed

    Lu, Xixin; Huangfu, Xiaoliu; Zhang, Xiang; Wang, Yaan; Ma, Jun

    2015-06-01

    Removal of trace mercury from aqueous solution by Mn (hydr)oxides formed in situ during coagulation with poly-aluminum chloride (PAC) (in situ MnO(x) combined with PAC) was investigated. The efficiency of trace mercury removal was evaluated under the experimental conditions of reaction time, Mn dosage, pH, and temperature. In addition, the ionic strength and the initial mercury concentration were examined to evaluate trace mercury removal for different water qualities. The results clearly demonstrated that in situ MnO(x) combined with PAC was effective for trace mercury removal from aqueous solution. A mercury removal ratio of 9.7 μg Hg/mg Mn was obtained at pH 3. Furthermore, at an initial mercury concentration of 30 μg/L and pH levels of both 3 and 5, a Mn dosage of 4 mg/L was able to lower the mercury concentration to meet the standards for drinking water quality at less than 1 μg/L. Analysis by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy suggests that the hydroxyls on the surface of Mn (hydr)oxides are the active sites for adsorption of trace mercury from aqueous solution. PMID:26042971

  15. Potentiometric determination of anhydrous aluminum chloride

    SciTech Connect

    Kofman, A.G.; Chernysh, G.V.; Vorozhtsov, G.N.

    1987-12-20

    Anhydrous aluminum chloride is a strong Lewis acid, widely used as a catalyst, in the synthesis and analysis of organic products. The aim of this article is to develop a potentiometric method of determining anhydrous AlCl/sub 3/. To estimate the validity of the results of the determination, use was made of French, Japanese, and Soviet samples of AlCl/sub 3/ with a known content of the main substance. The titration was performed in ethylene glycol. The procedure makes it possible to investigate the activity of AlCl/sub 3/ as a catalyst in different organic solvents

  16. The Structure of Nickel Chloride in the Ionic Liquid 1-Ethyl-3-methyl Imidazolium Chloride/Aluminum Chloride: X-ray Absorption Spectroscopy

    SciTech Connect

    D Roeper; K Pandya; G Cheek; W OGrady

    2011-12-31

    The structure of anhydrous nickel chloride in the ionic liquid 1-ethyl-3-methyl imidazolium chloride and aluminum chloride has been investigated with extended X-ray absorption fine structure (EXAFS) in both Lewis acid and Lewis base solutions. The EXAFS data of NiCl{sub 2} {center_dot} 6H{sub 2}O crystals were also recorded and analyzed to demonstrate the difference file technique. The difference file technique is used to obtain the structural information for the very closely spaced coordination shells of chloride and oxygen in NiCl{sub 2} {center_dot} 6H{sub 2}O and they are found to agree very closely with the X-ray diffraction data. The difference file technique is then used to analyze the nickel chloride in the ionic liquid solutions. Even though anhydrous NiCl{sub 2} is more soluble in the basic solution than in the acidic solution, the EXAFS data show a single coordination of four chlorides in a tetrahedron around the nickel atom in the basic solution. In a weak acid solution, there are six chlorides in a single octahedral coordination shell around the nickel. However, in a strong acid solution, in addition to the octahedral chloride-coordination shell, there is a second coordination shell of eight aluminum atoms in the form of a simple cube.

  17. REMOVAL OF CHLORIDE FROM AQUEOUS SOLUTIONS

    DOEpatents

    Schulz, W.W.

    1959-08-01

    The removal of chlorides from aqueons solutions is described. The process involves contacting the aqueous chloride containing solution with a benzene solution about 0.005 M in phenyl mercuric acetate whereby the chloride anions are taken up by the organic phase and separating the organic phase from the aqueous solutions.

  18. Structure of complexes between aluminum chloride and other chlorides, 2: Alkali-(chloroaluminates). Gaseous complexes

    NASA Technical Reports Server (NTRS)

    Hargittai, M.

    1980-01-01

    The structural chemistry of complexes between aluminum chloride and other metal chlorides is important both for practice and theory. Condensed-phase as well as vapor-phase complexes are of interest. Structural information on such complexes is reviewed. The first emphasis is given to the molten state because of its practical importance. Aluminum chloride forms volatile complexes with other metal chlorides and these vapor-phase complexes are dealt with in the second part. Finally, the variations in molecular shape and geometrical parameters are summarized.

  19. Corrosion-electrochemical properties of the anodic oxide films formed on aluminum in a chloride-nitrate melt in a 0.5 M Aqueous NaCl solution

    NASA Astrophysics Data System (ADS)

    Elshina, L. A.; Malkov, V. B.; Kudyakov, V. Ya.; Gnedenkov, S. V.; Sinebryukhov, S. L.; Egorkin, V. S.; Mashtalyar, D. V.

    2014-02-01

    The corrosion-electrochemical behavior of aluminum is studied in a chloride-nitrate melt containing 50 wt % eutectic mixture of cesium and sodium chlorides and 50 wt % sodium nitrate in the temperature range 790-900 K in an argon atmosphere.

  20. Effect of grain-boundary corrosion on impedance characteristics of an aluminum-zinc-indium alloy in 3.5% sodium chloride solution

    SciTech Connect

    Venugopal, A.; Angal, R.D.; Raja, V.S.

    1996-02-01

    Applications of Al alloy sacrificial anodes for cathodic protection (CP) of steel structures in marine environments are well known. Small changes in composition and heat treatment can affect the corrosion behavior of the alloy substantially. However, characterization of the alloy anodes in relation to such changes is lacking in the literature. Electrochemical impedance spectroscopy (EIS) was used to understand the dissolution behavior of an Al-Zn-In alloy in 3.5% sodium chloride (NaCl) solution as a function of time after the alloy was subjected to galvanostatic dissolution. Compared to optical microscopy, the changing trend in impedance spectra reflected the preferential dissolution of the alloy along the grain boundaries. The usefulness of EIS as a tool to indicate the current efficiency loss from grain-boundary attack was illustrated.

  1. Production of anhydrous aluminum chloride composition and process for electrolysis thereof

    DOEpatents

    Vandegrift, George F.; Krumpelt, Michael; Horwitz, E. Philip

    1983-01-01

    A process for producing an anhydrous aluminum chloride composition from a water-based aluminous material such as a slurry of aluminum hydroxide in a multistage extraction process in which the aluminum ion is first extracted into an organic liquid containing an acidic extractant and then extracted from the organic phase into an alkali metal chloride or chlorides to form a melt containing a mixture of chlorides of alkali metal and aluminum. In the process, the organic liquid may be recycled. In addition, the process advantageously includes an electrolysis cell for producing metallic aluminum and the alkali metal chloride or chlorides may be recycled for extraction of the aluminum from the organic phase.

  2. Aluminum chloride and membrane potentials of barley root cells

    SciTech Connect

    Etherton, B.; Shane, M.

    1986-04-01

    Aluminum chloride at pH 4 hyperpolarizes the membrane potentials of barley root epidermal cells. The authors tested to see whether this hyperpolarization could be caused by an aluminum induced alteration of the permeability of the membrane to potassium or sodium ions by measuring the effect of .04 mM aluminum ions (the Ca/sup + +/ conc. was 0.1 mM) on the membrane potential changes induced by changing the potassium or sodium concentrations in the medium bathing the roots. Aluminum ions did not change the magnitude of potassium or sodium induced changes in membrane potentials but significantly altered the rates of potassium and sodium induced changes of the potential. The results indicate that aluminum ions did not change sodium or potassium ion permeabilities of barley root cells.

  3. An XAFS Study of Niobium chloride in the ionic liquid 1-ethyl-3-methyl imidazolium chloride/ aluminum chloride

    SciTech Connect

    D Roeper; K Pandya; G Cheek; W OGrady

    2011-12-31

    Niobium chloride was studied with extended X-ray absorption fine structure spectroscopy (EXAFS) in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride (EMIC) ionic liquids. Although anhydrous Nb2Cl10 is more soluble in the basic melt than in the acidic melt, the EXAFS data shows that the coordination shell around the niobium does not change in the different ionic liquids. Both the acidic and basic melts show a coordination of five chlorides in the first shell. This indicates that in this series of ionic liquids, the Nb2Cl10 breaks up into two NbCl5 entities in both the acidic and the basic melts.

  4. 40 CFR 415.10 - Applicability; description of the aluminum chloride production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... aluminum chloride production subcategory. 415.10 Section 415.10 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Aluminum Chloride Production Subcategory § 415.10 Applicability; description of the aluminum chloride production subcategory. The provisions of this subpart are applicable to discharges...

  5. 40 CFR 415.10 - Applicability; description of the aluminum chloride production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... aluminum chloride production subcategory. 415.10 Section 415.10 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Aluminum Chloride Production Subcategory § 415.10 Applicability; description of the aluminum chloride production subcategory. The provisions of this subpart are applicable to discharges...

  6. 40 CFR 415.10 - Applicability; description of the aluminum chloride production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... aluminum chloride production subcategory. 415.10 Section 415.10 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Aluminum Chloride Production Subcategory § 415.10 Applicability; description of the aluminum chloride production subcategory. The provisions of this subpart are applicable to discharges...

  7. 40 CFR 415.10 - Applicability; description of the aluminum chloride production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... aluminum chloride production subcategory. 415.10 Section 415.10 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Aluminum Chloride Production Subcategory § 415.10 Applicability; description of the aluminum chloride production subcategory. The provisions of this subpart are applicable to discharges...

  8. 40 CFR 415.10 - Applicability; description of the aluminum chloride production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... aluminum chloride production subcategory. 415.10 Section 415.10 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Aluminum Chloride Production Subcategory § 415.10 Applicability; description of the aluminum chloride production subcategory. The provisions of this subpart are applicable to discharges...

  9. Water structure in concentrated lithium chloride solutions

    NASA Astrophysics Data System (ADS)

    Tromp, R. H.; Neilson, G. W.; Soper, A. K.

    1992-06-01

    The radial pair distribution functions gHH(r) and gOH(r) (to a good approximation) of 1 and 10 m solutions of lithium chloride in water have been obtained from neutron diffraction. It turns out that the intermolecular water structure in a solution of 10 m is affected considerably by the presence of ions—the number of hydrogen bonds is about 70% lower than in pure water. The intermolecular water structure in 1 m lithium chloride as well as the intramolecular water structure in both 1 and 10 m lithium chloride is not distinguishable from that of pure water in any measurable extent.

  10. XAFS Studies of Ni Ta and Nb Chlorides in the Ionic Liquid 1-Ethyl-3-Methyl Imidazolium Chloride / Aluminum Chloride

    SciTech Connect

    W OGrady; D Roeper; K Pandya; G Cheek

    2011-12-31

    The structures of anhydrous nickel, niobium, and tantalum chlorides have been investigated in situ in acidic and basic ionic liquids (ILs) of 1-methyl-3-ethylimidazolium chloride (EMIC)/AlCl{sub 3} with X-ray absorption spectroscopy (XAS). The coordination of NiCl{sub 2} changes from tetrahedral in basic solution to octahedral in acidic solution. The NiCl{sub 2} is a strong Lewis acid in that it can induce the AlCl{sub 3} to share its chlorides in the highly acidic IL, forming a structure with six near Cl{sup -} ions and eight further distant Al ions which share the chloride ions surrounding the Ni{sup 2+}. When Nb{sub 2}Cl{sub 10}, a dimer, is added to the acidic or basic solution, the dimer breaks apart and forms two species. In the acid solution, two trigonal bipyramids are formed with five equal chloride distances, while in the basic solution, a square pyramid with four chlorides forming a square base and one shorter axial chloride bond. Ta{sub 2}Cl{sub 10} is also a dimer and divides into half in the acidic solution and forms two trigonal bipyramids. In the basic solution, the dimer breaks apart but the species formed is sufficiently acidic that it attracts two additional chloride ions and forms a seven coordinated tantalum species.

  11. Lead chloride crystal growth from boiling solutions

    NASA Astrophysics Data System (ADS)

    Veintemillas-Verdaguer, S.; Rodríguez-Clemente, R.; Torrent-Burgues, J.

    1993-03-01

    Lead chloride single crystals can be grown from boiling solutions using KNO3-H20 solutions as a solvent. Crystals of 1 mm size produced by gel-growth technique were used as seeds. The solubility of PbC12 increases almost linearly with the KNO3 molality being 0.63m in a 7m KNO3 aqueous solutions at 105°C and pH = 2.6; this increase is related to the decrease of the activity coefficient of lead chloride in these solutions. In the first experiments, the supersaturation was attained by solvent extraction, but due to the simultaneous changes in the concentration of the KNO3 mineralizer during the extraction, the growth rate was irregular and defective crystals were obtained. The experimental set-up was therefore modified and a transport technique was added to the system in order to feed the boiling reactor continuously with fresh lead chloride solution. The growth of the crystals takes place at constant concentration of KNO3 in these new conditions. With this experimental modification, isometric PbCI2 crystals of up to lcm size were obtained in three weeks. The observed morphology is close to that calculated by Woensdregt and Hartmann [J. Crystal Growth 87(1988)561].

  12. Electrochemical and spectroscopic studies of sulfur in aluminum chloride-N-(n-butyl)pyridinium chloride

    SciTech Connect

    Marassi, R.; Laher, T.M.; Mamantov, G.; Trimble, D.S.

    1985-07-01

    The behavior of sulfur in aluminum chloride-N-(n-butyl)pyridinium chloride (AlCl/sub 3/-BPC) was studied using Raman spectroscopy and electrochemical techniques. In basic (BPC-rich) melts, sulfur can be reduced to sulfide, probably in the form of an AlSCl-like species. No oxidation to positive oxidation states of sulfur is observed in basic melts. In acidic (AlCl/sub 3/-rich) melts, sulfur can be oxidized to S(I) and eventually to S(IV), which is only stabl in the melt for short periods of time. No reduction to sulfide-like species or formation of low oxidation states is observed in acidic melts.

  13. Distribution of aluminum species and the characteristics of structure of poly-aluminum-chloride-sulfate(PACS).

    PubMed

    Gao, B Y; Yue, Q Y; Yu, H; Wang, Y

    2001-01-01

    A series of poly-aluminum-chloride-sulfate (PACS), which has different basicities (gamma) and Al3+/SO4(2-) molar ratio, has been prepared and dried at 105 degrees C and 65 degrees C, respectively. The distribution of aluminum species of PACS was examined, and the effect of gamma value, Al3+/SO4(2-) molar ratio, dilution on the distribution of aluminum species of PACS was also investigated by using Alferron timed complex colorimetric method. The IR spectroscopy and X-ray diffraction were used to study the effect of gamma value, Al3+/SO4(2-) molar ratio and the drying temperature on the structure of PACS. The experimental results show that Al3+/SO4(2-) molar ratio has a great effect on the distribution of aluminum species, but the dilution has a little effect on the distribution of aluminum species. The lower the Al3+/SO4(2-) molar ratio, the higher the proportions of the polymer and colloidal species in PACS. The polymeric degree of PACS was related to gamma value and Al3+/SO4(2-) molar ratio. Drying temperature has an influence on the structure and the solubility of solid PACS products. PMID:11590710

  14. Solid propellant exhausted aluminum oxide and hydrogen chloride - Environmental considerations

    NASA Technical Reports Server (NTRS)

    Cofer, W. R., III; Winstead, E. L.; Purgold, G. C.; Edahl, R. A.

    1993-01-01

    Measurements of gaseous hydrogen chloride (HCl) and particulate aluminum oxide (Al2O3) were made during penetrations of five Space Shuttle exhaust clouds and one static ground test firing of a shuttle booster. Instrumented aircraft were used to penetrate exhaust clouds and to measure and/or collect samples of exhaust for subsequent analyses. The focus was on the primary solid rocket motor exhaust products, HCl and Al2O3, from the Space Shuttle's solid boosters. Time-dependent behavior of HCl was determined for the exhaust clouds. Composition, morphology, surface chemistry, and particle size distributions were determined for the exhausted Al2O3. Results determined for the exhaust cloud from the static test firing were complicated by having large amounts of entrained alkaline ground debris (soil) in the lofted cloud. The entrained debris may have contributed to neutralization of in-cloud HCl.

  15. Hydrolysis of ferric chloride in solution

    SciTech Connect

    Lussiez, G.; Beckstead, L.

    1996-11-01

    The Detox{trademark} process uses concentrated ferric chloride and small amounts of catalysts to oxidize organic compounds. It is under consideration for oxidizing transuranic organic wastes. Although the solution is reused extensively, at some point it will reach the acceptable limit of radioactivity or maximum solubility of the radioisotopes. This solution could be cemented, but the volume would be increased substantially because of the poor compatibility of chlorides and cement. A process has been developed that recovers the chloride ions as HCl and either minimizes the volume of radioactive waste or permits recycling of the radioactive chlorides. The process involves a two-step hydrolysis at atmospheric pressure, or preferably under a slight vacuum, and relatively low temperature, about 200{degrees}C. During the first step of the process, hydrolysis occurs according to the reaction below: FeCl{sub 3 liquid} + H{sub 2}O {r_arrow} FeOCl{sub solid} + 2 HCl{sub gas} During the second step, the hot, solid, iron oxychloride is sprayed with water or placed in contact with steam, and hydrolysis proceeds to the iron oxide according to the following reaction: 2 FeOCl{sub solid} + H{sub 2}O {r_arrow} Fe{sub 2}O{sub 3 solid} + 2 HCl{sub gas}. The iron oxide, which contains radioisotopes, can then be disposed of by cementation or encapsulation. Alternately, these chlorides can be washed off of the solids and can then either be recycled or disposed of in some other way.

  16. REMOVAL OF CHLORIDE FROM AQUEOUS SOLUTIONS

    DOEpatents

    Hyman, M.L.; Savolainen, J.E.

    1960-01-01

    A method is given for dissolving reactor fuel elements in which the uranium is associated with a relatively inert chromium-containing alloy such as stainless steel. An aqueous mixture of acids comprising 2 to 2.5 molar hydrochloric acid and 4 to 8 molar nitric acid is employed in dissolving the fuel element. In order io reduce corrosion in subsequent processing of the resulting solution, chloride values are removed from the solution by contacting it with concentrated nitric acid at an elevated temperature.

  17. Elastin Calcification and its Prevention with Aluminum Chloride Pretreatment

    PubMed Central

    Vyavahare, Narendra; Ogle, Matthew; Schoen, Frederick J.; Levy, Robert J.

    1999-01-01

    Elastin, an abundant structural protein present in the arterial wall, is prone to calcification in a number of disease processes including porcine bioprosthetic heart valve calcification and atherosclerosis. The mechanisms of elastin calcification are not completely elucidated. In the present work, we demonstrated calcification of purified elastin in rat subdermal implants (Ca2+ = 89.73 ± 9.84 μg/mg after 21 days versus control, unimplanted Ca2+ = 0.16 ± 0.04 μg/mg). X-ray diffraction analysis along with resolution enhanced FTIR spectroscopy demonstrated the mineral phase to be a poorly crystalline hydroxyapatite. We investigated the time course of calcification, the effect of glutaraldehyde crosslinking on calcification, and mechanisms of inhibition of elastin calcification by pretreatment with aluminum chloride (AlCl3). Glutaraldehyde pretreatment did not affect calcification (Ca2+ = 89.06 ± 17.93 μg/mg for glutaraldehyde crosslinked elastin versus Ca2+ = 89.73 ± 9.84 μg/mg for uncrosslinked elastin). This may be explained by radioactive (3H) glutaraldehyde studies showing very low reactivity between glutaraldehyde and elastin. Our results further demonstrated that AlCl3 pretreatment of elastin led to complete inhibition of elastin calcification using 21-day rat subdermal implants, irrespective of glutaraldehyde crosslinking (Ca2+ = 0.73–2.15 μg/mg for AlCl3 pretreated elastin versus 89.73 ± 9.84 for untreated elastin). The AlCl3 pretreatment caused irreversible binding of aluminum ions to elastin, as assessed by atomic emission spectroscopy. Moreover, aluminum ion binding altered the spatial configuration of elastin as shown by circular dichroism (CD), Fourier transform infrared (FTIR), and 13C nuclear magnetic resonance (NMR) spectroscopy studies, suggesting a net structural change including a reduction in the extent of β sheet structures and an increase in coil-turn conformations. Thus, it is concluded that purified elastin calcifies in rat

  18. Effect of chlorides on solution corrosivity of methyldiethanolamine (MDEA) solutions

    SciTech Connect

    Rooney, P.C.; Bacon, T.R.; DuPart, M.S.; Willbanks, K.D.

    1997-08-01

    Solution corrosivity of MDEA/water solutions containing added HCl or NaCl have been measured by weight loss coupons at 250 F and by linear polarization resistance (LPR) at 208 F using carbon steel, 304SS, 316SS and 410SS. General corrosion as well as pitting or crevice corrosion tendencies were recorded for each species. Based on these results, recommendations are made for chlorides in MDEA that minimizes corrosion in gas treating operations.

  19. Astaxanthin ameliorates aluminum chloride-induced spatial memory impairment and neuronal oxidative stress in mice.

    PubMed

    Al-Amin, Md Mamun; Reza, Hasan Mahmud; Saadi, Hasan Mahmud; Mahmud, Waich; Ibrahim, Abdirahman Adam; Alam, Musrura Mefta; Kabir, Nadia; Saifullah, A R M; Tropa, Sarjana Tarannum; Quddus, A H M Ruhul

    2016-04-15

    Aluminum chloride induces neurodegenerative disease in animal model. Evidence suggests that aluminum intake results in the activation of glial cells and generation of reactive oxygen species. By contrast, astaxanthin is an antioxidant having potential neuroprotective activity. In this study, we investigate the effect of astaxanthin on aluminum chloride-exposed behavioral brain function and neuronal oxidative stress (OS). Male Swiss albino mice (4 months old) were divided into 4 groups: (i) control (distilled water), (ii) aluminum chloride, (iii) astaxanthin+aluminum chloride, and (iv) astaxanthin. Two behavioral tests; radial arm maze and open field test were conducted, and OS markers were assayed from the brain and liver tissues following 42 days of treatment. Aluminum exposed group showed a significant reduction in spatial memory performance and anxiety-like behavior. Moreover, aluminum group exhibited a marked deterioration of oxidative markers; lipid peroxidation (MDA), nitric oxide (NO), glutathione (GSH) and advanced oxidation of protein products (AOPP) in the brain. To the contrary, co-administration of astaxanthin and aluminum has shown improved spatial memory, locomotor activity, and OS. These results indicate that astaxanthin improves aluminum-induced impaired memory performances presumably by the reduction of OS in the distinct brain regions. We suggest a future study to determine the underlying mechanism of astaxanthin in improving aluminum-exposed behavioral deficits. PMID:26927754

  20. ALUMINUM CHLORIDE EFFECT ON Ca2+,Mg(2+)-ATPase ACTIVITY AND DYNAMIC PARAMETERS OF SKELETAL MUSCLE CONTRACTION.

    PubMed

    Nozdrenko, D M; Abramchuk, O M; Soroca, V M; Miroshnichenko, N S

    2015-01-01

    We studied enzymatic activity and measured strain-gauge contraction properties of the frog Rana temporaria m. tibialis anterior muscle fascicles during the action of aluminum chloride solution. It was shown that AlCl3 solutions did not affect the dynamic properties of skeletal muscle preparation in concentrations less than 10(-4) M Increasing the concentration of AlCl3 to 10(-2) M induce complete inhibition of muscle contraction. A linear correlation between decrease in Ca2+,Mg(2+)-ATPase activity of sarcoplasmic reticulum and the investigated concentrations range of aluminum chloride was observed. The reduction in the dynamic contraction performance and the decrease Ca2+,Mg(2+)-ATPase activity of the sarcoplasmic reticulum under the effect of the investigated AlCl3 solution were minimal in pre-tetanus period of contraction. PMID:26717594

  1. Properties and coagulation performance of coagulant poly-aluminum-ferric-silicate-chloride in water and wastewater treatment.

    PubMed

    Gao, Bao-yu; Yue, Qin-yan; Wang, Bing-jian

    2006-01-01

    An efficient inorganic polymer coagulant, poly-aluminum-ferric-silicate-chloride (PAFSC), was developed using two approaches: (i) hydroxylation of the mixture of AlCl3, FeCl3 and fresh polysilicic acid in different Al/Fe/Si molar ratios to obtain PAFSCc and (ii) hydroxylated poly-aluminum-iron-chloride (PAFC) combined with aged polysilicic acid in different Al/Fe/Si ratios to produce PAFSCm. The properties of PAFSC in comparison with polyaluminum silicate chloride (PASC) and polyferric silicate chloride (PAFC) were characterized by various experimental methods. The effect of Al/Fe/Si molar ratio on the hydrolysis-polymerization process of Al (III) and Fe (III) in PAFSC solutions was examined by pH titration, and the effect of Al/Fe/Si molar ratio on electrokinetic mobility of PAFSC was studied by Zeta potential measurement. The laboratory experiments were performed to evaluate the PAFSC in comparison with polyaluminum chloride (PAC) for the coagulation of synthetic water samples, actual surface water and wastewater. The results show that interactions exist among aluminum species, ferric species and polysilicic acid, and the Al/Fe/Si molar ratio affects the Zeta potential of the hydrolyzate and the coagulating performance. PAFSC achieved a better water treatment result than PAC. At the same basicity (B) value and Al/Fe/Si ratio, PAFSCc has better coagulation performance than PAFSCm. PAFSC is a new type and high efficiency composite inorganic polymer coagulant. PMID:16854802

  2. Anodizing And Sealing Aluminum In Nonchromated Solutions

    NASA Technical Reports Server (NTRS)

    Emmons, John R.; Kallenborn, Kelli J.

    1995-01-01

    Improved process for anodizing and sealing aluminum involves use of 5 volume percent sulfuric acid in water as anodizing solution, and 1.5 to 2.0 volume percent nickel acetate in water as sealing solution. Replaces process in which sulfuric acid used at concentrations of 10 to 20 percent. Improved process yields thinner coats offering resistance to corrosion, fatigue life, and alloy-to-alloy consistency equal to or superior to those of anodized coats produced with chromated solutions.

  3. Tissue distribution of subcutaneously administered aluminum chloride in weanling rabbits

    SciTech Connect

    Du Val, G.; Grubb, B.R.; Bentley, P.J.

    1986-01-01

    The purpose of the investigation was to determine blood and tissue levels of aluminum (Al) in normal young rabbits. Furthermore, tissue distribution and accumulation of Al were determined as related to blood concentration in Al-dosed rabbits. The levels of Al accumulated were determined in different tissues of growing rabbits after continuous subcutaneous administration of Al chloride (3.78 mg/d) for 28 d. No signs of toxicity were apparent from comparisons of hematocrit or weight gain between control and Al-dosed rabbits. The largest concentration of the Al was observed in bone, which was also found to have the highest levels in the control rabbit tissues. Following bone, the experimental animals showed the greatest increase of Al levels in kidney cortex, kidney medulla, liver, testes, skeletal muscle, heart, brain white matter, and brain hippocampus, in that order. No significant difference was found in brain grey matter between control and experimental animals. As the brain tissue of the Al-treated animals had the lowest Al level of the tissues measured, it appears that there is a partial blood-brain barrier to entry of Al.

  4. 46 CFR 151.50-75 - Ferric chloride solution.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Ferric chloride solution. 151.50-75 Section 151.50-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-75 Ferric chloride solution. A containment system (cargo tank...

  5. The electrowinning of copper from a cupric chloride solution

    NASA Astrophysics Data System (ADS)

    Lin, H. K.; Wu, X. J.; Rao, P. D.

    1991-08-01

    In this work, the Eh pCl diagram of the CuCl-H2O system was established, and the kinetics of copper dissolution in cupric chloride solution were studied with an emphasis on possible difficulties that may occur during copper electrowinning. The results were used to guide an investigation of copper electrowinning from cupric chloride solution.

  6. Efficacy and Safety of Aluminum Chloride in Controlling External Hemorrhage: An Animal Model Study

    PubMed Central

    Nouri, Saeed; Sharif, Mohammad Reza; Panahi, Yunes; Ghanei, Mostafa; Jamali, Bardia

    2015-01-01

    Background: Despite all the progress in surgical science, bleeding caused by traffic accidents is still one of the challenges surgeons face in saving patients’ lives. Therefore, introducing an effective method to control external bleeding is an important research priority. Objectives: This study aimed to compare the hemostatic effect of aluminum chloride versus simple suturing in controlling external bleeding. Materials and Methods: This experimental study was conducted in Kashan, Iran. In this study, 60 male Wistar rats were randomly allocated into six groups. An incision, two centimeters (cm) long and half a cm deep, was made on each rat’s shaved back skin and the hemostatic time was measured once using aluminum chloride with different concentrations (5%, 10%, 15%, 25%, and 50%) and then using the control method (controlling hemorrhage by simple suturing). The skin tissue was assessed for pathological changes. Results: The hemostatic time of aluminum chloride 50%, 25%, 15%, 10% and 5% were 8.20 ± 0.919, 14.10 ± 1.37, 21.20 ± 1.31, 30.80 ± 1.68 and 42.00 ± 4.19 seconds, respectively. Also, the mean hemostasis time in the control group (suture) was 84.00 ± 4.05 seconds. The hemostatic times of different concentrations of aluminum chloride were significantly less than that of the control group. There was a statistically significant difference between every two hemostatic time. The pathologic examination showed the highest frequency of low-grade inflammation based on the defined pathological grading. Conclusions: The aluminum chloride method needs less time to control external hemorrhage compared to the control method (controlling external hemorrhage by simple suturing). Aluminum chloride is an effective agent in controlling external hemorrhage in an animal model. PMID:25964855

  7. Spectrofluorimetric determination of thallium in silicate rocks with rhodamine b in the presence of aluminum chloride

    USGS Publications Warehouse

    Shnepfe, M.M.

    1975-01-01

    A sensitive spectrofluorimetric procedure with rhodamine B in the presence of aluminum chloride is given for determining submicrogram and microgram quantities of thallium in silicate rocks. Samples are decomposed with a mixture of hydrofluoric and nitric acids and then treated with hydrochloric acid. Thallium is extracted as its dithizonate with chloroform from an alkaline medium containing ascorbate, citrate, and cyanide and then back-extracted with dilute nitric acid. After destruction of the organic matter and treatment with bromine, hydrochloric acid, aluminum chloride, and rhodamine B, the {A table is presented}. ?? 1975.

  8. 46 CFR 151.50-75 - Ferric chloride solution.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Ferric chloride solution. 151.50-75 Section 151.50-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-75 Ferric chloride...

  9. 46 CFR 151.50-75 - Ferric chloride solution.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Ferric chloride solution. 151.50-75 Section 151.50-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-75 Ferric chloride...

  10. 46 CFR 151.50-75 - Ferric chloride solution.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Ferric chloride solution. 151.50-75 Section 151.50-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-75 Ferric chloride...

  11. 46 CFR 151.50-75 - Ferric chloride solution.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Ferric chloride solution. 151.50-75 Section 151.50-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-75 Ferric chloride...

  12. Microstructural Evolution of Chloride-Cleaned Silicon Carbide Aluminum Composites

    NASA Astrophysics Data System (ADS)

    Adeosun, S. O.; Akpan, E. I.; Gbenebor, O. P.; Balogun, S. A.

    2016-02-01

    This study examines the synergy between reinforcement surface modifications on the evolution of microstructures of AA6011-silicon carbide particle (SiCp) composites in multidirectional solidification. Silicon carbide particles (SiCp) were cleaned with ammonium chloride, tin(II) chloride, sodium chloride, and palladium(II) chloride and used as reinforcement to cast AA6011-SiCp composites by applying the stir casting method. A scanning electron microscope and x-ray diffractometer were used to investigate the morphology and phases present, respectively, in the composite material. Results show that wetting agents were effective as they inhibited the formation of Al4C3 in all modified composites. The modified SiCp was found to have varying effects on the morphology, dendrite arm size and direction, size and configuration of AlFeSi, and the amount of eutectic silicon depending on the concentration of the reagent and cleaning time. The highest effect was shown by the use of 40 g/L of tin(II) chloride. The composites had short dendritic arms, good interfacial interaction, and only a few crystals of AlFeSi.

  13. Ultrastructural alterations of Erwinia carotovora subsp. atroseptica caused by treatment with aluminum chloride and sodium metabisulfite.

    PubMed

    Yaganza, Elian-Simplice; Rioux, Danny; Simard, Marie; Arul, Joseph; Tweddell, Russell J

    2004-11-01

    Aluminum and bisulfite salts inhibit the growth of several fungi and bacteria, and their application effectively controls potato soft rot caused by Erwinia carotovora. In an effort to understand their inhibitory action, ultrastructural changes in Erwinia carotovora subsp. atroseptica after exposure (0 to 20 min) to different concentrations (0.05, 0.1, and 0.2 M) of these salts were examined by using transmission electron microscopy. Plasma membrane integrity was evaluated by using the SYTOX Green fluorochrome that penetrates only cells with altered membranes. Bacteria exposed to all aluminum chloride concentrations, especially 0.2 M, exhibited loosening of the cell walls, cell wall rupture, cytoplasmic aggregation, and an absence of extracellular vesicles. Sodium metabisulfite caused mainly a retraction of plasma membrane and cellular voids which were more pronounced with increasing concentration. Bacterial mortality was closely associated with SYTOX stain absorption when bacteria were exposed to either a high concentration (0.2 M) of aluminum chloride or prolonged exposure (20 min) to 0.05 M aluminum chloride or to a pH of 2.5. Bacteria exposed to lower concentrations of aluminum chloride (0.05 and 0.1 M) for 10 min or less, or to metabisulfite at all concentrations, did not exhibit significant stain absorption, suggesting that no membrane damage occurred or it was too weak to allow the penetration of the stain into the cell. While mortality caused by aluminum chloride involves membrane damage and subsequent cytoplasmic aggregation, sulfite exerts its effect intracellularly; it is transported across the membrane by free diffusion of molecular SO2 with little damage to the cellular membrane. PMID:15528547

  14. Reducing phosphorus in swine effluent with aluminum chloride treatment during lagoon cleanout

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) runoff from agricultural lands fertilized with swine manure can be a significant environmental issue. The objective of this study was to evaluate the effect of aluminum chloride (AlCl3) applications to a swine lagoon during total clean out on P concentrations in manure and runoff wat...

  15. Reducing ammonia emissions and volatile fatty acids in poultry litter with liquid aluminum chloride

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was a pen trial in which the effects of adding different rates of liquid aluminum chloride (AlCl3) on litter pH, total volatile fatty acids (VFAs), and ammonia (NH3) fluxes was evaluated. Liquid AlCl3 treatments used in this study were sprayed on the rice hull surface at rates of 100 g, 2...

  16. Electrolytic conditioning of a magnesium aluminum chloride complex for reversible magnesium deposition

    DOE PAGESBeta

    Barile, Christopher J.; Barile, Elizabeth C.; Zavadil, Kevin R.; Nuzzo, Ralph G.; Gewirth, Andrew A.

    2014-12-04

    We describe in this report the electrochemistry of Mg deposition and dissolution from the magnesium aluminum chloride complex (MACC). The results define the requirements for reversible Mg deposition and definitively establish that voltammetric cycling of the electrolyte significantly alters its composition and performance. Elemental analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (SEM-EDS) results demonstrate that irreversible Mg and Al deposits form during early cycles. Electrospray ionization-mass spectrometry (ESI-MS) data show that inhibitory oligomers develop in THF-based solutions. These oligomers form via the well-established mechanism of a cationic ring-opening polymerization of THF during the initial synthesis of the MACC andmore » under resting conditions. In contrast, MACC solutions in 1,2-dimethoxyethane (DME), an acyclic solvent, do not evolve as dramatically at open circuit potential. Furthermore, we propose a mechanism describing how the conditioning process of the MACC in THF improves its performance by both tuning the Mg:Al stoichiometry and eliminating oligomers.« less

  17. Electrolytic conditioning of a magnesium aluminum chloride complex for reversible magnesium deposition

    SciTech Connect

    Barile, Christopher J.; Barile, Elizabeth C.; Zavadil, Kevin R.; Nuzzo, Ralph G.; Gewirth, Andrew A.

    2014-12-04

    We describe in this report the electrochemistry of Mg deposition and dissolution from the magnesium aluminum chloride complex (MACC). The results define the requirements for reversible Mg deposition and definitively establish that voltammetric cycling of the electrolyte significantly alters its composition and performance. Elemental analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (SEM-EDS) results demonstrate that irreversible Mg and Al deposits form during early cycles. Electrospray ionization-mass spectrometry (ESI-MS) data show that inhibitory oligomers develop in THF-based solutions. These oligomers form via the well-established mechanism of a cationic ring-opening polymerization of THF during the initial synthesis of the MACC and under resting conditions. In contrast, MACC solutions in 1,2-dimethoxyethane (DME), an acyclic solvent, do not evolve as dramatically at open circuit potential. Furthermore, we propose a mechanism describing how the conditioning process of the MACC in THF improves its performance by both tuning the Mg:Al stoichiometry and eliminating oligomers.

  18. SOLVENT EXTRACTION PROCESS FOR URANIUM FROM CHLORIDE SOLUTIONS

    DOEpatents

    Blake, C.A. Jr.; Brown, K.B.; Horner, D.E.

    1960-05-24

    An improvement was made in a uranium extraction process wherein the organic extractant is a phosphine oxide. An aqueous solution containing phosphate ions or sulfate ions together with uranium is provided with a source of chloride ions during the extraction step. The presence of the chloride ions enables a phosphine oxide to extract uranium in the presence of strong uranium- complexing ions such as phosphate or sulfate ions.

  19. Evaluation of localized corrosion of zirconium in acidic chloride solutions

    SciTech Connect

    Fahey, J.; Holmes, D.; Yau, T.L.

    1997-01-01

    Zirconium is prone to localized corrosion in acidic chloride (Cl{sup {minus}}) solutions contaminated by oxidizing ions, such as ferric or cupric ions. This tendency can be reduced by ensuring that the zirconium surface is clean and smooth. The effect of surface condition on localized corrosion of zirconium in acidic chloride solutions was predicted using potentiodynamic polarization scans. Predictions were confirmed by mass-loss tests on various combinations of surface finish and acid concentrations. A real-time indication of localized corrosion was derived by monitoring electrochemical noise produced between two similar electrodes immersed in an acidic chloride solution. Electrochemical noise monitoring correlated well with predictions from the potentiodynamic polarization and mass-loss experiments. Electrochemical noise results showed a more anodic potential caused by ferric ion (Fe{sup 3+}) contamination might be necessary for localized corrosion but that it was not a sufficient condition. A clean zirconium surface reduced localized corrosion of zirconium.

  20. Treatment of automotive wastewater by coagulation-flocculation using poly-aluminum chloride (PAC), ferric chloride (FeCl3) and aluminum sulfate (alum)

    NASA Astrophysics Data System (ADS)

    Bakar, Abdul Fattah Abu; Halim, Azhar Abdul

    2013-11-01

    A physicochemical treatment (coagulation-flocculation) was applied for automotive wastewater using poly-aluminum chloride (PAC), ferric chloride (FeCl3) and aluminum sulfate (alum) aided by anionic polyacrylamide as flocculant to determine the effectiveness of coagulation method for removal of COD, TSS and heavy metals (Fe, Ni and Zn). The results obtained proved that PAC was comparatively more efficient to FeCl3 and alum. At defined optimum experiment condition (coagulant dose: 70 mg/L, coagulant aid dose: 2 mg/L and pH 7), PAC showed 70% removal for (chemical oxygen demand) COD and 98% of (total suspended solid) TSS. For FeCl3 and alum, the maximum removal for COD were 64% and 54%, meanwhile TSS removal were 91% and 94%. Heavy metals removal using PAC also showed better results in which produced 98% of iron removal, 83% of zinc removal and 63% of nickel removal under optimum condition. The comparison revealed that the use of PAC aided by anionic polyacrylamide produced higher removal for COD, TSS and heavy metals compared to FeCl3 and alum for automotive wastewater treatment.

  1. Effect of chloride incorporation on the crystallization of zirconium-barium-lanthanum-aluminum fluoride glass

    NASA Technical Reports Server (NTRS)

    Neilson, G. F.; Smith, G. L.; Weinberg, M. C.

    1985-01-01

    One aspect of the influence of preparation procedure on the crystallization behavior of a zirconium-barium-lanthanum-aluminum fluoride glass was studied. The crystallization pattern of this glass may be affected by the chlorine concentration within it. In particular, when such glasses are heated at low temperatures, the alpha-Ba-Zr-F6 crystalline phase forms only in those glasses which contain chloride.

  2. SOLVENT-FREE TETRAHYDROPYRANYLATION (THP) OF ALCOHOLS AND PHENOLS AND THEIR REGENERATION BY CATALYTIC ALUMINUM CHLORIDE HEXAHYDRATE

    EPA Science Inventory

    Catalytic amount of aluminum chloride hexahydrate enables solvent-free tetrahydropyranylation (THP) of alcohols and phenols at moderate temperatures. A simple addition of methanol helps to regenerate the corresponding alcohols and phenols thus rendering these protection and depro...

  3. Composition of aqueous extracts of broiler litter treated with aluminum sulfate, ferrous sulfate, ferric chloride and gypsum.

    PubMed

    Tasistro, Armando S; Kissel, David E

    2006-01-01

    More knowledge on the composition of aqueous extracts of broiler litter amended for Water Soluble P (WSP) reduction would help to understand how amendments work. We measured pH, concentrations of Ca, Mg, Fe, Al, Cu, Mn, Zn, Molybdate Reactive P (MRP), and Dissolved Unreactive P (DUP) in water extracts of broiler litter treated with aluminum sulfate (ALS), ferrous sulfate (FES), ferric chloride (FEC), and gypsum (GYP) at 0, 5, 15, and 25% w/w. In order to study the effects of acidification, the same properties were measured in aqueous extracts of broiler litter suspensions that were titrated to end-points 3, 4, or 6 with 0.5N HCl. Concentrations of MRP, DUP, Ca and Mg, were 61%, 53%, 3.8 times, and 2.6 times greater in extracts from suspensions acidified to pH 6 than at the original pH of 8.9. ALS, FES, and FEC reduced pH, and showed similar effects on WSP concentrations, which were greater than with GYP. The magnitude of the reductions in WSP by ALS, FES, and FEC is uncertain because the actual amount of WSP immobilized cannot be determined. This is because of two opposite effects: 1) Through adsorption, soluble aluminum and iron remove phosphates from solution, and 2) Through acidification, iron and aluminum compounds release phosphates to solution. PMID:16893785

  4. REMOVAL OF CHLORIDE FROM ACIDIC SOLUTIONS USING NO2

    SciTech Connect

    Visser, A; Robert Pierce, R; James Laurinat, J

    2006-08-22

    Chloride (Cl{sup -}) salt processing in strong acids is used to recycle plutonium (Pu) from pyrochemical residues. The Savannah River National Laboratory (SRNL) is studying the potential application of nitrogen dioxide (NO{sub 2}) gas to effectively convert dissolved pyrochemical salt solutions to chloride-free solutions and improve recovery operations. An NO{sub 2} sparge has been shown to effectively remove Cl{sup -} from solutions containing 6-8 M acid (H{sup +}) and up to 5 M Cl{sup -}. Chloride removal occurs as a result of the competition of at least two reactions, one which is acid-dependent. Below 4 M H+, NO2 reacts with Cl- to produce nitrosyl chloride (ClNO). Between 6 M and 8 M H{sup +}, the reaction of hydrochloric acid (HCl) with nitric acid (HNO{sub 3}), facilitated by the presence of NO{sub 2}, strongly affects the rate of Cl{sup -} removal. The effect of heating the acidic Cl{sup -} salt solution without pre-heating the NO{sub 2} gas has minimal effect on Cl{sup -} removal rates when the contact times between NO{sub 2} and the salt solution are on the order of seconds.

  5. Study of aluminum corrosion in aluminum solar heat collectors using aqueous glycol solution for heat transfer. Annual technical progress report, July 30, 1979-July 31, 1980

    SciTech Connect

    Wong, D.; Cocks, F.H.

    1980-08-01

    The effects of glycol aging at elevated temperatures over long periods of time were studied and the zinc powder protective technique was optimized. Glycols are known to gradually decompose into organic acids at high temperatures. These product species may be aggressive to aluminum in the long run. In addition, corrosion inhibitors may also breakdown due to continuous exposure to high temperatures. As for the zinc powder protective technique, efforts have been made to determine the optimal conditions under which aluminum solar collector panels can be protected most effectively and economically. Both uninhibited and inhibited ethylene as well as propyleneglycols have been aged at three different temperatures (100, 140, and 190/sup 0/C) for 6000 hours continuously. Aliquot samples were taken at 1000 hour intervals for pH measurement and chemical analysis. Results showed that in most cases solution pH dropped sharply during the first 1000 hours of exposure and gradually decreased at a slower pace as the aging process progressed. It was also noted that higher temperatures appeared to hasten this pH shift. The corrosiveness of these aged glycol solutions towards aluminum was determined based on laboratory corrosion tests. The critical pitting potential (E/sub p/) of aluminum in chloride-ion containing aqueous glycol solutions was determined. Its dependence on temperature, chloride-ion concentration, and glycol content was investigated in detail. E/sub p/ was found to become more negative with higher chloride-ion concentration, increasing temperature, and decreasing glycol content. (MHR)

  6. New uses for calcium chloride solution as a mounting medium.

    PubMed

    Herr, J M

    1992-01-01

    Fresh cross sections of stems (Psilotum nudum, Coleus blumei, and Pelargonium peltatum) and roots (Setcreasea purpurea) 120 microns thick were fixed in FPA50 (formalin: propionic acid: 50% ethanol, 5:5:90, v/v) for 24 hr and stored in 70% ethanol. The sections were transferred to water and then to 1% phloroglucin in 20% calcium chloride solution plus either hydrochloric, nitric, or lactic acid in the following ratios of phloroglucin-CaCl2 solution:acid: 25:4, 20:2, or 15:5. The sections were mounted on slides either in one of the three mixtures or in fresh 20% calcium chloride solution. A rapid reaction of the acid-phloroglucin with lignin produced a deep red color in tracheary elements and an orange-red color in sclerenchyma. Fixed and stored leaf pieces from Nymphaea odorata were autoclaved in lactic acid, washed in two changes of 95% ethanol, transferred to water, and treated with the three acid-phloroglucin-calcium chloride mixtures. The abundant astrosclereids stained an orange-red color similar to that of sclerenchyma in the sections. In addition, a new method is reported for specifically staining lignified tissues. When sections or leaf pieces are stained in aqueous 0.05% toluidine blue O, then placed in 20% calcium chloride solution, all tissues destain except those with lignified or partially lignified cell walls. Thus, toluidine blue O applied as described becomes a reliable specific test for lignin comparable to the acid-phloroglucin test. PMID:1377501

  7. Acid hydrolysis of cellulose in zinc chloride solution

    SciTech Connect

    Cao, N.J.; Xu, Q.; Chen, L.F.

    1995-12-31

    The efficient conversion of cellulosic materials to ethanol has been hindered by the low yield of sugars, the high energy consumption in pretreatment processes, and the difficulty of recycling the pre-treatment agents. Zinc chloride may provide an alternative for pre-treating biomass prior to the hydrolysis of cellulose. The formation of a zinc-cellulose complex during the pretreatment of cellulose improves the yield of glucose in both the enzymatic and acid hydrolysis of cellulose. Low-temperature acid hydrolysis of cellulose in zinc chloride solution is carried out in two stages, a liquefaction stage and a saccharification stage. Because of the formation of zinc-cellulose complex in the first stage, the required amount of acid in the second stage has been decreased significantly. In 67% zinc chloride solution, a 99.5% yield of soluble sugars has been obtained at 70{degrees}C and 0.5M acid concentration. The ratio of zinc chloride to cellulose has been reduced from 4.5 to 1.5, and the yield of soluble sugars is kept above 80%. The rate of hydrolysis is affected by the ratio of zinc chloride to cellulose, acid concentration, and temperature.

  8. Tetragonal Chicken Egg White Lysozyme Solubility in Sodium Chloride Solutions

    NASA Technical Reports Server (NTRS)

    Forsythe, Elizabeth L.; Judge, Russell A.; Pusey, Marc L.

    1998-01-01

    The solubility of chicken egg white lysozyme, crystallized in the tetragonal form was measured in sodium chloride solutions from 1.6 to 30.7 C, using a miniature column solubility apparatus. Sodium chloride solution concentrations ranged from 1 to 7% (w/v). The solutions were buffered with 0.1 M sodium acetate buffer with the solubility being measured at pH values in 0.2 pH unit increments in the range pH 4.0 to 5.4, with data also included at pH 4.5. Lysozyme solubility was found to increase with increases in temperature and decreasing salt concentration. Solution pH has a varied and unpredictable effect on solubility.

  9. Properties of a new liquid desiccant solution - Lithium chloride and calcium chloride mixture

    SciTech Connect

    Ertas, A.; Anderson, E.E.; Kiris, I. )

    1992-09-01

    Desiccants, broadly classified as solid and liquid desiccants, have the property of extracting and retaining moisture from air brought into contact with them. By using either type, moisture in the air is removed and the resulting dry air can be used for air-conditioning or drying purposes. Because of its properties, lithium chloride is the most stable liquid desiccant and has a large dehydration concentration (30% to 45%), but its cost is relatively high ($9.00-13.00 per kg). It is expected that lithium chloride will reduce the relative humidity to as low as 15%. Calcium chloride is the cheapest (45 cents per kg) and most readily available desiccant, but it has the disadvantage of being unstable depending on the air inlet conditions and the concentration of the desiccant in the solution. To stabilize calcium chloride and to decrease the high cost of lithium chloride, the two can be mixed in different weight combinations. The main objective of this research is to measure the physical properties of different combinations of this mixture such as density, viscosity, and vapor pressure which are necessary for analysis of heat and mass transfer in a packed tower desiccant-air contact system. The solubility of this new liquid desiccant under certain temperature-concentrations will also be studied.

  10. Absorption characteristics of elemental mercury in mercury chloride solutions.

    PubMed

    Ma, Yongpeng; Xu, Haomiao; Qu, Zan; Yan, Naiqiang; Wang, Wenhua

    2014-11-01

    Elemental mercury (Hg(0)) in flue gases can be efficiently captured by mercury chloride (HgCl2) solution. However, the absorption behaviors and the influencing effects are still poorly understood. The mechanism of Hg(0) absorption by HgCl2 and the factors that control the removal were studied in this paper. It was found that when the mole ratio of Cl(-) to HgCl2 is 10:1, the Hg(0) removal efficiency is the highest. Among the main mercury chloride species, HgCl3(-) is the most efficient ion for Hg(0) removal in the HgCl2 absorption system when moderate concentrations of chloride ions exist. The Hg(0) absorption reactions in the aqueous phase were investigated computationally using Moller-Plesset perturbation theory. The calculated Gibbs free energies and energy barriers are in excellent agreement with the results obtained from experiments. In the presence of SO3(2-) and SO2, Hg(2+) reduction occurred and Hg(0) removal efficiency decreased. The reduced Hg(0) removal can be controlled through increased chloride concentration to some degree. Low pH value in HgCl2 solution enhanced the Hg(0) removal efficiency, and the effect was more significant in dilute HgCl2 solutions. The presence of SO4(2-) and NO3(-) did not affect Hg(0) removal by HgCl2. PMID:25458680

  11. Chemical milling solution produces smooth surface finish on aluminum

    NASA Technical Reports Server (NTRS)

    Lorenzen, H. C.

    1966-01-01

    Elementary sulfur mixed into a solution of caustic soda and salts produces an etchant which will chemically mill end-grain surfaces on aluminum plate. This composition results in the least amount of thickness variation and pitting.

  12. An equilibrium model for chloride removal from recycled cooling water using the ultra-high lime with aluminum process.

    PubMed

    Abdel-Wahab, Ahmed; Batchelor, Bill; Schwantes, Jon

    2005-01-01

    Removal of chloride from recycled cooling water is needed to reduce corrosion and prolong equipment life. Laboratory experiments have demonstrated that the ultra-high lime with aluminum (UHLA) process has the ability to achieve high chloride removal efficiency from recycled cooling water. In an effort to further understand the behavior of chloride in the UHLA process, a fundamental model of the chemical processes was developed. The purpose of this paper is to describe this equilibrium model and present values for solubility products of precipitated solids that have not been investigated previously. The model was based on PHREEQC and a new program called INVRS K was integrated with PHREEQC to calculate values of unknown or poorly defined equilibrium or kinetic constants using a Gauss-Newton nonlinear regression routine. Model predictions indicated that the results could be best described by assuming the formation of a solid solution of calcium chloroaluminate (Ca4Al2Cl2OH12), tricalcium hydroxyaluminate (Ca3Al2OH12), and tetracalcium hydroxyaluminate (Ca4Al2OH14). PMID:16381154

  13. [Analysis and stability of suxamethonium chloride. 2: Study of various factors in the stability of suxamethonium chloride injection solutions].

    PubMed

    Kottke, D; Döge, G; Pohloudek-Fabini, R

    1983-06-01

    The packing material (glass ampoules and plastic disposable syringes) and the degree of purity of the active agent do not affect the stability of injectable suxamethonium chloride solutions. In contrast to this, the stability was markedly improved by lowering the temperature of storage. Injectable suxamethonium chloride solutions may be stored in plastic disposable syringes. PMID:6611640

  14. Multi-scale modelling of uranyl chloride solutions

    SciTech Connect

    Nguyen, Thanh-Nghi; Duvail, Magali Villard, Arnaud; Dufrêche, Jean-François; Molina, John Jairo; Guilbaud, Philippe

    2015-01-14

    Classical molecular dynamics simulations with explicit polarization have been successfully used to determine the structural and thermodynamic properties of binary aqueous solutions of uranyl chloride (UO{sub 2}Cl{sub 2}). Concentrated aqueous solutions of uranyl chloride have been studied to determine the hydration properties and the ion-ion interactions. The bond distances and the coordination number of the hydrated uranyl are in good agreement with available experimental data. Two stable positions of chloride in the second hydration shell of uranyl have been identified. The UO{sub 2}{sup 2+}-Cl{sup −} association constants have also been calculated using a multi-scale approach. First, the ion-ion potential averaged over the solvent configurations at infinite dilution (McMillan-Mayer potential) was calculated to establish the dissociation/association processes of UO{sub 2}{sup 2+}-Cl{sup −} ion pairs in aqueous solution. Then, the association constant was calculated from this potential. The value we obtained for the association constant is in good agreement with the experimental result (K{sub UO{sub 2Cl{sup +}}} = 1.48 l mol{sup −1}), but the resulting activity coefficient appears to be too low at molar concentration.

  15. Effect of chromuium, aluminum, and titanium on the corrosion resistance of nickel in molten sodium sulfate and chloride

    SciTech Connect

    Oryshich, I.V.

    1985-09-01

    The author reports on a study whose purpose was to determine the corrosion of binary nickel alloys, containing aluminum, titanium and chromium, in molten sodium sulfate and chloride. The work was undertaken because under operating conditions, gas-turbine materials are subject to oxidation and high-temperature corrosion caused by contact with molten salt based on sodium sulfate formed during fuel combustion. It is concluded that: on alloying nickel with chromium, resistance to sulfide corrosion increases, but with aluminum and titanium it is reduced; alloying nickel with aluminum, titanium (up to 6-8 %) and chromium (up to 10-12 %) leads to an increase in its resistance to the action of molten sodium chloride; and, binary Ni-Al, Ni-Ti and ternary Ni-Al-Ti alloys have a lower corrosion resistance in sodium solfate than in sodium chloride.

  16. Effects of organic solutes on chemical reactions of aluminum

    USGS Publications Warehouse

    Lind, Carol J.; Hem, John David

    1975-01-01

    Concentrations of organic matter in the general range of 1-10 milligrams per litre organic carbon are common in natural water, and many naturally occurrin7 organic compounds form aluminum complexes. The aluminum concentrations in near-neutral pH solutions may be 10-100 times higher than the values predicted from solubility data if formation of such organic complexes is ignored. The processes of polymerization of aluminum hydroxide and precipitation of gibbsite are inhibited by the presence of the organic flavone compound quercetin in concentrations as low as 10 x -5.3 mole per litre. Quercetin forms a complex, with a probable molar ratio of 1:2 aluminum to quercetin, that has a formation constant (f12) of about 10 12. A complex with a higher aluminum-quercetin ratio also was observed, but this material tends to evolve into a compound of low solubility that removes aluminum from solution. In the presence of both dissolved aluminum and aqueous silica, low concentrations of quercetin improved the yield of crystallized kaolinite and halloysite. Small amounts of well-shaped kaolinite and halloysite crystals were identified by electron microscopy in solutions with pH's in the range 6.5-8.5 after 155 days aging in one experimer t and 481 days aging in a repeated experiment. The bulk of the precipitated material was amorphous to X-rays, and crystalline material was too small a proportion of the total to give identifiable X-ray diffraction peaks. The precipitates had aluminum-silicon ratios near 1, and their solubility corresponded to that found by Hem, Roberson, Lind, and Polzer (1973) for similar aluminosilicate precipitated in the absence of organic solutes. The improved yield of crystalline material obtained in the presence of quercetin probably is the result of the influence of the organic compound on the aluminum hydroxide polymerization process. Natural water containing color imparted by organic material tends to be higher in aluminum than would be predicted by p

  17. Pitting corrosion of iron in weakly alkaline chloride solutions

    SciTech Connect

    Makar, G.L.; Tromans, D.

    1996-04-01

    Chloride-induced pitting corrosion of iron at pH 10.5 and 25 C was examined by conducting quasi-steady-state (potentiostatic) polarization experiments in borate-buffered 0.1 M sodium chloride solutions with buffer concentrations from 0 M to 0.075 M. Values of the film breakdown potential (E{sub b}) were scattered at each buffer concentration, and the scatter band moved to higher potentials with increasing concentrations, indicating increased resistance to pitting. Consistent with this, pitting did not always occur at the higher buffer concentrations. E{sub b} measurements, optical and electron microscopy, X-ray microanalysis, and supplementary polarization experiments in lower-pH borate solutions suggested pitting in the iron -Cl{sup {minus}} system initiated within occluded regions, such as matrix-inclusion interfaces and exposed voids, where pH control was lost because of an inadequate local supply of buffer species. Pitting behavior was consistent with a mechanism dominated by mass transport, in which the presence of Cl{sup {minus}} prevented buffering of occluded regions by the borate specie H{sub 2}BO{sub 3}{sup {minus}}, allowing the ph to be driven into an acidic domain where the solubilities of ferrous hydroxide and ferric hydroxide are high.

  18. Compaction and multiple chain assembly of DNA with the cationic polymer poly(aluminum chloride) (PAC).

    PubMed

    Matsuzawa, Yukiko; Kanbe, Toshio; Yoshikawa, Kenichi

    2004-07-20

    Assembly of DNA molecules by the addition of poly(aluminum chloride) (PAC) was studied. In the absence of PAC, electron microscopy indicated the formation of elongated coiled DNA molecules. In the presence of PAC, multiple doughnut-like structures, 8-15 nm thick, formed and fused together. When salt was added, the doughnut-like structures tended to be thinner and the morphology of the fused doughnuts became irregular. We obtained a view of a single DNA structure by fluorescent microscopy, which revealed that individual DNA molecules undergo a discrete transition from an elongated to compacted state with an increase in PAC concentration. Electron microscopic observation showed that a regular doughnut is the typical structure seen under low salt conditions. At high salt concentrations, the doughnut shape deformed, yielding results similar to those produced by the salt effect on DNA assembly at high DNA concentrations. PMID:15248734

  19. The use of synthetic hydrocalcite as a chloride-ion getter for a barrier aluminum anodization process

    SciTech Connect

    Panitz, J.K.G.; Sharp, D.J.

    1995-11-01

    Chloride ion contamination at parts per billion concentrations plaques electrochemists studying barrier anodic aluminum oxide film growth and anodic aluminum oxide capacitor manufacturers. Chloride ion contamination slows film growth and reduces film quality. We have demonstrated that synthetic hydrocalcite substantially reduces the detrimental effects of chloride ion contamination in an aqueous electrolyte commonly used to grow barrier anodic aluminum oxide. We have determined that problems arise if precautions are not taken when using synthetic hydrocalcite as a chloride-ion getter in an aqueous electrolyte. Synthetic hydrocalcite is somewhat hydrophobic. If this powder is added directly to an aqueous electrolyte, some powder disperses; some floats to the top of the bath and forms scum that locally impedes anodic film formation. Commercially available powder contains a wide range of particle sizes including submicrometer-sized particles that can escape through filters into the electrolyte and cause processing problems. These problems can be over come if (1) the getter is placed in filter bags, (2) a piece of filter paper is used to skim trace amounts of getter floating on the top of the bath, (3) dummy runs are performed to scavenge chloride-ion loaded getter micelles dispersed in the bath, and (4) substrates are rinsed with a strong stream of deionized water to remove trace amounts of powder after anodization.

  20. Aluminum-chloride-phthalocyanine encapsulated in liposomes: activity against naturally occurring dog breast cancer cells.

    PubMed

    Rocha, Martha S T; Lucci, Carolina M; Longo, João Paulo F; Galera, Paula D; Simioni, Andreza R; Lacava, Zulmira G M; Tedesco, Antônio C; Azevedo, Ricardo B

    2012-04-01

    Breast tumors represent the most common malignant tumors. Current treatments for humans and pets rely on tumor excision and adjuvant chemotherapy, which may affect both cancer cells and normal cells. Photodynamic therapy (PDT) is an approved treatment modality for a variety of cancers and was recently recommended as a first-line treatment for non-melanoma skin cancers for humans. The main purpose of the present study was to determine the efficacy of PDT using aluminum-chloride-phthalocyanine that is encapsulated in liposomes and LED as a light source to kill naturally occurring female dog breast cancer in vitro. The cytotoxicity behavior of the encapsulated photosensitizer in the dark and under irradiation using the 670 nm laser were investigated using classical trypan blue and MTT cell viability tests, acridine orange and ethidium bromide staining to label organelles, and cell morphology. Cell morphology was evaluated using light and electron microscopy. Our results demonstrate a reduced cell viability that is associated with morphologic alterations. The neoplasic cell destruction was predominantly mediated via a necrotic process, which was assayed using acridine orange and ethidium bromide staining. These findings were confirmed using light and electronic microscopy. The photosensitizer or laser irradiation alone did not induce cytotoxicity or morphological alterations, indicating the safety and efficacy of PDT with chloro-aluminum-phthalocyanine that was encapsulated in liposomes for the treatment of breast cancer cells in vitro. PMID:22515076

  1. Effects of aluminum chloride on serum proteins, bilirubin, and hepatic trace elements in chickens.

    PubMed

    Wang, Ben; Zhu, Yanzhu; Zhang, Hongling; Liu, Liming; Li, Guojiang; Song, Yongli; Li, Yanfei

    2016-09-01

    The aim of this study was to reveal the effects of aluminum chloride (AlCl3) on the hepatic metabolism function and trace elements' distribution. Two hundred healthy male chickens (1 day old) were intraperitoneally administered with AlCl3 (0, 18.31, 27.47, and 36.62 mg kg(-1) day(-1) of Al(3+)) consecutively for 3 days. Then the chickens were allowed to rest for 1 day. The cycle lasted four days. The cycle was repeated 15 times (60 days). The contents of serum total protein (TP), albumin (ALB), total bilirubin (TBI), direct bilirubin (DBI), hepatic aluminum (Al), copper (Cu), iron (Fe), and zinc (Zn) were examined. The results showed that the contents of serum TP and ALB and hepatic Fe and Zn decreased and the contents of serum TBI and DBI and hepatic Al and Cu increased in the chickens with AlCl3 This indicates that chronic administration of AlCl3 impairs the hepatic metabolism function and disorders the hepatic trace elements' distribution. PMID:25896954

  2. Lipid vesicles loading aluminum phthalocyanine chloride: Formulation properties and disaggregation upon intracellular delivery.

    PubMed

    Calori, Italo Rodrigo; Tedesco, Antonio Claudio

    2016-07-01

    Aluminum phthalocyanine chloride (AlClPc) is a second-generation photodynamic therapy (PDT) photosensitizer characterized for its high hydrophobicity and self-aggregation tendency in aqueous media, which hamper its potential application. Aiming at AlClPc solubilization we proposed here the use of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) at different proportions to form mixed lipid vesicles (LVs) as a drug delivery system. LVs were prepared by ethanol injection method and formed nano-sized vesicles (about 100nm) with suitable polydispersity index, negative zeta potential, and stable in aqueous medium for at least 50days. AlClPc strongly interacts with LV (high binding constant values), especially due to aluminum-phosphate specific interactions, which gives a surface localization to AlClPc molecules as demonstrated by fluorescence quenching data. Anisotropy, static and time-resolved fluorescence measurements corroborated with these results and demonstrated that AlClPc self-aggregation occurred even in the liposomes. However, formulation uptake by oral squamous cell carcinoma (OSCC) the AlClPc was distributed in cellular organelles and suffered a disaggregation process demonstrated by fluorescence life-time imaging microscopy. This amazing behavior is new and increases the scientific knowledge about the intracellular mechanism of action of PDT photosensitizers. In addition, these results open a new perspective to the potential use of AlClPc-LV formulations for photodynamic treatment. PMID:27130963

  3. MICROSTRUCTURE EVOLUTION MODELING FOR SOLUTION TREATMENT OF ALUMINUM ALLOYS

    SciTech Connect

    Yin, Hebi; Sabau, Adrian S; Skszek, Timothy; Niu, X

    2013-01-01

    The microstructure evolution during solution treatment plays an important role in mechanical properties of heat-treated aluminum alloys. In this paper, models were reviewed that can predict the microstructure evolution during the solutionizing process of the aging heat treatment of aluminum alloys. The dissolution of Mg2Si particles has been modeled as a diffusion process of Mg in the -Al matrix. The evolution of volumetric fraction of fragmented silicon as a function of time and temperature was also considered. The growth and coarsening of silicon particles during the heat treatment was considered. It was found that constitutive equations and required property data for most of the phenomena that need to be considered are available. Several model parameters that need to be obtained from material characterization were identified. Pending the availability of these model parameters, this comprehensive model can be used to describe the microstructure evolution of aluminum alloys in order to optimize the solutionizing heat treatment for energy savings.

  4. Representation of the solubility of lead chloride in various chloride solutions with Pitzer's model

    NASA Astrophysics Data System (ADS)

    Mgaidi, A.; Fürst, W.; Renon, H.

    1991-08-01

    A modified Pitzer’s model[6] has been applied to the representation of the activities of various species in chloride solutions of lead (II). The parameters associated with the representation were the formation constants of four lead chlorocomplexes as well as Pitzer’s interaction parameters. [7] They were determined by treatment of a data base composed of experimental solubilities of lead in NaCl, NH4C1, and HC1 solutions at 25 °C. The root mean square (rms) relative deviations obtained for the representation of the experimental solubilities were 7.8 pct, 5.6 pct, and 5.6 pct for the three systems, respectively. The extension of the model to solubilities in a NaClO4-NaCl solution at an apparent ionic strength of 4 mol/kg water gives a rms relative deviation of 8.9 pct if one parameter involving the perchlorate anion is adjusted. A data treatment of experimental solubilities at other temperatures (from 13 °C to 100 °C) for the systems PbCl2-NaCl-H2O and PbCl2-NH4Cl-H2O has been made to determine the temperature derivatives of Pitzer’s parameters involving complexed ions as well as the variation of solubility and complexation constants with temperature. The resulting rms relative deviation is 9.8 pct.

  5. Use of modified hydroxy-aluminum bentonites for chromium(III) removal from solutions.

    PubMed

    Volzone, Cristina; Beatriz Garrido, Liliana

    2008-09-01

    The retention of chromium(III) from a 2,000 ppm chromium basic sulfate and tannery waste solution at pH 4.5 using modified hydroxy-aluminum bentonites (OH-Al bentonites) as adsorbents was studied. OH-Al bentonite was prepared by mixing clay with a hydrolyzed commercial chlorohydroxy Al solution. The modified Al bentonites were obtained by (a) a treatment with 0.5M sodium chloride and (b) a treatment with a Na-hexametaphosphate solution (HMP) after adding sodium chloride. The effect of heating the adsorbents at 100, 500, 700 and 800 degrees C on Cr retention as a function of time was also analyzed. Cr retention by modified OH-Al bentonite with HMP increased with time (up to 100 mg Cr/g) where modified OH-Al bentonite was twice that of untreated bentonite. The relatively high uptake of metal from the salt solution by modified OH-Al bentonite treated at 800 degrees C, in which a complete interlayer collapse occurred, indicated the importance of the contribution of external surface sites to the retention capacity. The maximum Cr uptake from a water waste was 24 mg/g, due to interferences and different chromium species in the industrial solution. PMID:17900792

  6. Localized corrosion of candidate container materials in ferric chloride solutions

    SciTech Connect

    Roy, A.K.; Fleming, D.L.; Lum, B.Y.

    1999-07-01

    Localized corrosion behavior of candidate inner- and outer-container materials of current nuclear waste package design was evaluated in aqueous solutions of various concentrations of ferric chloride (FeCl{sub 3}) at 30 C, 60 C and 90 C using the electrochemical cyclic potentiodynamic polarization (CPP) technique. Materials tested include A 516 carbon steel (UNS K01800), and high-performance UNS N08825, UNS N06985, UNS N06030, UNS N06455, UNS N06625, UNS N06022, and UNS R53400. A 516 steel suffered from severe general and localized attack including pitting and crevice corrosion. High-nickel UNS N08825 and N06985 also became susceptible to severe pitting and crevice corrosion. The extent of localized attack was less pronounced in UNS N06030 and N06455. UNS N06625 experienced severe surface degradation including general corrosion crevice corrosion and intergranular attack. In contrast, only slight crevice corrosion tendency was observed with nickel-base UNS N06022 in solutions containing higher concentrations of FeCl{sub 3} at 60 C and 90 C. UNS R53400 was immune to localized attack in all tested environments. The test solutions showed a significant amount of precipitated particles, especially at higher temperatures.

  7. Localized corrosion of candidate container materials in ferric chloride solutions

    SciTech Connect

    Fleming, D L; Lum, B Y; Roy, A K

    1998-10-01

    Localized corrosion behavior of candidate inner and outer container materials of currently-designed nuclear waste package was evaluated in aqueous solutions of various concentrations of ferric chloride (FeCl{sub 3}) at 30 C, 60 C and 90 C using the electrochemical cyclic potentiodynamic polarization (CPP) technique. Materials tested include A 5 16 carbon steel and high-performance alloys 825, G-3, G-30, C-4, 625. C-22, and Ti Gr-12. A 516 steel suffered from severe general and localized attack including pitting and crevice corrosion. High-nickel alloys 825 and G-3 also became susceptible to severe pitting and crevice corrosion. The extent of localized attack was less pronounced in alloys G-30 and C-4. Alloy 625 experienced severe surface degradation including general corrosion, crevice corrosion and intergranular attack. In contrast, only a slight crevice corrosion tendency was observed with nickel-base alloy C-22 in solutions containing higher concentrations of FeCl{sub 3} at 60 C and 90 C. Ti Gr-12 was immune to localized attack in all tested environments. The test solutions showed significant amount of precipitated particles during and after testing especially at higher temperatures.

  8. Anodic dissolution of nickel in acidic chloride solutions

    NASA Astrophysics Data System (ADS)

    El Aal, E. E. Abd; Zakria, W.; Diab, A.; El Haleem, S. M. Abd

    2003-04-01

    The anodic dissolution of nickel was studied galvanostatically in hydrochloric acid solutions of various concentrations. The reaction orders of chloride ion and hydrogen ion concentrations were found to be 0.5 and 1.0, respectively. An anodic Tafel slope equal to 120 ± 10 mV · decade-1 was obtained. The dissolution rate of nickel at constant acid concentration was increased with stirring of the solution and increasing temperature. The activation energy, ΔH, for the anodic dissolution process was found to be 12 kcal · mol-1. The presence of oxygen in solutions assisted the passivation process. The effect of addition of aniline and some of its derivatives (o-, m-, and p-anisidine) as inhibitors on the dissolution kinetics of Ni in 1 M HCl was also investigated. These compounds inhibited the anodic dissolution of nickel without affecting the Tafel slope, indicating that the adsorption of such inhibitors could not interfere with the mechanism of metal dissolution.

  9. Form and stability of aluminum hydroxide complexes in dilute solution

    USGS Publications Warehouse

    Hem, John David; Roberson, Charles Elmer

    1967-01-01

    Laboratory studies of solutions 4.53 x 10 -4 to 4.5 x 10 -5 molal (12.2-1.2 ppm) in aluminum, in 0.01 molal sodium perchlorate, were conducted to obtain information as to the probable behavior of aluminum in natural water. When the solutions were brought to pH 7.5-9.5 and allowed to stand for 24 hours, a precipitate was obtained which was virtually amorphous as shown by X-rays, and which had a solubility equivalent to that of boehmite. This precipitate had a hydrolysis constant (*Ks4) of 1.93 x 10 -13a. When solutions were allowed to stead at this pH range for 10 days, their precipitates gave the X-ray pattern of bayerite (*Ks4 = 1.11 > (10- 4). These hydrolysis constants were obtained at 25?C. and corrected to zero ionic strength and are in close agreement with other published values. The predominant dissolved form in this pH range is Al(OH) -4. Below neutral pH (7.0) the dissolved aluminum species consist of octahedral units in which each aluminum ion is surrounded by six water molecules or hydroxide ions. Single units such as Al(OH2)6 + 3 and AlOH(OH2)5+2 are most abundant below pH 5.0, and where the molar ratio (r) of combined hydroxide to total dissolved aluminum is low. When r is greater than 1.0, polymerization of the octahedral units occurs. When r is between 2.0 and 3.0, solutions aged for 10 days or more contained colloidal particles between 0.10 and 0.45 ? in diameter. Particles whose diameters were greater than 0.10 ? were identified by X-ray diffraction as gibbsite. Particles smaller than 0.10 ? were also present and were shown by means of the electron microscope to have a hexagonal crystal pattern. Structured material consisting of sheets of coalesced six-membered rings of aluminum ions held together by double OH bridges has a distinctive kinetic behavior. This property was used to determine amounts of polymerized material in solutions having r between 1.0 and 3.0 after aging times ranging from a few hours to more than 4 months. Aging increased the

  10. Fisetin enhances behavioral performances and attenuates reactive gliosis and inflammation during aluminum chloride-induced neurotoxicity.

    PubMed

    Prakash, Dharmalingam; Gopinath, Kulasekaran; Sudhandiran, Ganapasam

    2013-03-01

    Aluminum (Al) is an environmental neurotoxin that affects cerebral functions and causes health complications. However, the role of Al in arbitrating glia homeostasis and pathophysiology remains obscure. Astrocyte, microglia activation (reactive gliosis), and associated inflammatory events play a decisive role in neurodegeneration and may represent a target for treating neurodegenerative disorders. In this study, we have analyzed the role of aluminum chloride (AlCl3) in causing reactive gliosis in the brain of mice and the ability of fisetin, a flavonoid to attenuate reactive gliosis and neuronal inflammation. Reports suggest that fisetin exerts antioxidant and anti-inflammatory actions. Fisetin at a dose of 15 mg/kg body weight was orally administered, daily (pre-treated for 4 weeks before AlCl3 induction and co-treated until experimental period of 8 weeks) to mice induced with AlCl3 (200 mg/kg b.wt./day/8 weeks, orally). Administration of AlCl3 developed behavioral deficits, triggered lipid peroxidation (LPO), compromised acetylcholine esterase (AChE) activity, and reduced the levels of superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), and reduced glutathione (GSH), and caused histologic aberrations. These effects were accompanied by increased expressions of Glial fibrillary acidic protein and ionized calcium-binding adapter molecule 1. Pro-inflammatory cytokines, such as tumor necrosis factor alpha, interleukin-1β, inducible nitric oxide synthase, were increased upon AlCl3 administration. AlCl3-induced alterations in the activities of SOD, CAT, GST, AChE and levels of GSH, LPO, activity of AChE, behavioral deficits, histologic aberrations, reactive gliosis, and inflammatory niche were attenuated on treatment with fisetin. Collectively, our results indicate that fisetin exerts neuroprotection against AlCl3-induced brain pathology. PMID:23315010

  11. Polyene Formation Catalyzed by Phosphotungstic Acid and Aluminum Chloride in Thin Films of Poly(Vinyl Alcohol)

    NASA Astrophysics Data System (ADS)

    Tretinnikov, O. N.; Sushko, N. I.; Maly, A. B.

    2016-01-01

    Formation of linear polyenes -(CH=CH) n - during thermal dehydration of thin layers (9-20 μm) of poly(vinyl alcohol) containing phosphotungstic-acid and aluminum-chloride catalysts was investigated. It was found that the concentration of long-chain ( n ≥ 8) polyenes in films containing phosphotungstic acid increased smoothly with increasing annealing time although the kinetics of the dehydration were independent of the film thickness. The polyene ( n ≥ 8) formation rate in films containing aluminum chloride dropped quickly with decreasing film thickness and increasing annealing time. As a result, long-chain polyenes practically did not form regardless of the annealing time for a film thickness of 11 μm.

  12. Purification of aqueous plutonium chloride solutions via precipitation and washing.

    SciTech Connect

    Stroud, M. A.; Salazar, R. R.; Abney, Kent David; Bluhm, E. A.; Danis, J. A.

    2003-01-01

    Pyrochemical operations at Los Alamos Plutonium Facility (TA-55) use high temperature melt s of calcium chloride for the reduction of plutonium oxide to plutonium metal and hi gh temperature combined melts of sodium chloride and potassium chloride mixtures for the electrorefining purification of plutonium metal . The remaining plutonium and americium are recovered from thes e salts by dissolution in concentrated hydrochloric acid followed by either solvent extraction or io n exchange for isolation and ultimately converted to oxide after precipitation with oxalic acid . Figur e 1 illustrates the current aqueous chloride flow sheet used for plutonium processing at TA-55 .

  13. Investigation of aluminum gate CMP in a novel alkaline solution

    NASA Astrophysics Data System (ADS)

    Cuiyue, Feng; Yuling, Liu; Ming, Sun; Wenqian, Zhang; Jin, Zhang; Shuai, Wang

    2016-01-01

    Beyond 45 nm, due to the superior CMP performance requirements with the metal gate of aluminum in the advanced CMOS process, a novel alkaline slurry for an aluminum gate CMP with poly-amine alkali slurry is investigated. The aluminum gate CMP under alkaline conditions has two steps: stock polishing and fine polishing. A controllable removal rate, the uniformity of aluminum gate and low corrosion are the key challenges for the alkaline polishing slurry of the aluminum gate CMP. This work utilizes the complexation-soluble function of FA/O II and the preference adsorption mechanism of FA/O I nonionic surfactant to improve the uniformity of the surface chemistry function with the electrochemical corrosion research, such as OCP-TIME curves, Tafel curves and AC impedance. The result is that the stock polishing slurry (with SiO2 abrasive) contains 1 wt.% H2O2,0.5 wt.% FA/O II and 1.0 wt.% FA/O I nonionic surfactant. For a fine polishing process, 1.5 wt.% H2O2, 0.4 wt.% FA/O II and 2.0 wt.% FA/O I nonionic surfactant are added. The polishing experiments show that the removal rates are 3000 ± 50 Å/min and 1600 ± 60 Å/min, respectively. The surface roughnesses are 2.05 ± 0.128 nm and 1.59 ± 0.081 nm, respectively. A combination of the functions of FA/O II and FA/O I nonionic surfactant obtains a controllable removal rate and a better surface roughness in alkaline solution.

  14. Effects of aluminum chloride on some trace elements and erythrocyte osmotic fragility in rats.

    PubMed

    Oztürk, Bahar; Ozdemir, Semra

    2015-12-01

    Aluminum (Al) is a nonessential, toxic element to which humans are constantly exposed as a result of an increase in industrialization and improving technology practices. The aim of the study was to investigate the effects of different durations and doses of Al exposure on serum and tissue element levels and erythrocyte osmotic fragility in rats. A total of 40 male Wistar Albino rats were divided into five groups: control, group I (3 weeks, 8 mg/kg), group II (6 weeks, 8 mg/kg), group III (3 weeks, 16 mg/kg), and group IV (6 weeks, 16 mg/kg). Al chloride (AlCl3) was injected intraperitoneally (i.p.) five times a week. At the end of the experimental period, levels of Al, iron (Fe), copper (Cu), and zinc (Zn) in serum, liver, and kidney tissues were measured using inductively coupled plasma optical emission spectrometry. Osmotic fragility was determined using a spectrophotometer. The results of the experiment indicate that Al induced a statistically significant increase in Al and Fe concentrations in liver and serum as well as in Cu in the kidney. The Fe concentration in serum and kidney tissues was significantly lower in all the groups. As a result of our study, it may be concluded that tissue Al accumulation may lead to an increase in osmotic fragility of erythrocytes and abnormal trace element levels. PMID:23625912

  15. Ultrastructural alterations in Fusarium sambucinum and Heterobasidion annosum treated with aluminum chloride and sodium metabisulfite.

    PubMed

    Avis, T J; Rioux, D; Simard, M; Michaud, M; Tweddell, R J

    2009-02-01

    Aluminum chloride (AlCl(3)) and sodium metabisulfite (Na(2)S(2)O(5)) have received increasing attention as antifungal agents for the control of plant diseases. In an effort to understand their toxic action on fungi, ultrastructural changes and membrane damage in Fusarium sambucinum (Ascomycota) and Heterobasidion annosum (Basidiomycota) in response to salt exposure was investigated using transmission electron microscopy. Conidial membrane damage was quantified using SYTOX Green stain, which only enters altered membranes. The results showed that mortality of the conidia was generally closely associated with SYTOX stain absorption in F. sambucinum treated with Na(2)S(2)O(5) and in H. annosum treated with AlCl(3) or Na(2)S(2)O(5), suggesting that these salts cause membrane alterations. For both fungi, ultrastructural alterations in conidia treated with AlCl(3) and Na(2)S(2)O(5) included membrane retraction, undulation, and invagination. At higher concentrations or exposure periods to the salts, loss of membrane integrity, cytoplasmic leakage, and cell rupture were observed. Ultrastructural alterations and increased SYTOX stain absorption in salt-treated conidia appear consistent with a mode of action where AlCl(3) and Na(2)S(2)O(5) alter membrane integrity and permeability. PMID:19159309

  16. Protective effect of resveratrol against aluminum chloride induced nephrotoxicity in rats

    PubMed Central

    Dera, Hussain S. Al

    2016-01-01

    Objectives: To investigate the potential protective effect of resveratrol (RES) on aluminum chloride (AlCl3)-induced nephrotoxicity in rats. Methods: This experimental study was conducted from April to June 2015 at the Medical College of King Khalid University, Abha, Kingdom of Saudi Arabia. The experiments were performed on 24 male Wistar rats. The rats were randomly allocated into 4 groups; 1) group A: control rats received only normal saline, 2) group B: received RES dissolved in normal saline, 3) group C: model group and received AlCl3 dissolved in normal saline and 4) group D: RES treated group and received concomitant doses of RES+AlCl3. All treatments were administered for consecutive 40 days. After 40 days of treatments, kidney function tests, oxidative stress parameters and histopathological assay were evaluated. Results: all findings clearly showed significant deteriorations in kidney function and architectures after AlCl3 exposure. This was accompanied by increased renal oxidative stress and inflammation suggesting strong pro-oxidant activity of AlCl3 in spite of its non-redox status. Resveratrol co-treatment with AlCl3 to the rats showed significant improvement in all biochemical and histological parameters related to kidney function and structure. Conclusion: The findings of the current study showed that RES pre-administration to rats ameliorates renal damage and improves renal function in AlCl3 intoxicated rats in a mechanism related to its antioxidant potential. PMID:27052279

  17. Vibrational spectroscopic analysis of aluminum phthalocyanine chloride. experimental and DFT study

    NASA Astrophysics Data System (ADS)

    Soliman, I. M.; El-Nahass, M. M.; Eid, Kh. M.; Ammar, H. Y.

    2016-06-01

    In this work, we report a combined experimental and theoretical study of aluminum phthalocyanine chloride (AlPcCl). The FT-IR and Raman spectra of AlPcCl were recorded and analyzed. The density functional theory (DFT) computations have been performed at B3LYP/6-31g and B3LYP/6-311g to derive equilibrium geometry, vibrational wavenumbers, intensity and NLO properties. All the observed vibrational bands have been discussed and assigned to normal mode or to combinations on the basis of our DFT calculations as a primary source of attribution and also by comparison with the previous results for similar compounds. The natural bond orbital (NBO) calculations were performed to study the atomic charge distribution of the investigated compound. The calculated results showed that dipole moment of the investigated compound was 4.68 Debye and HOMO-LUMO energy gap was 2.14 eV. The lowering of frontier orbital gap appears to be the cause of its enhanced charge transfer interaction.

  18. The neuroprotective role of boric acid on aluminum chloride-induced neurotoxicity.

    PubMed

    Colak, Suat; Geyikoglu, Fatime; Keles, Osman Nuri; Türkez, Hasan; Topal, Ahmet; Unal, Bünyami

    2011-09-01

    This study was designed to investigate the qualitative and quantitative changes in brain tissue following aluminum chloride (AlCl(3)) administration and to determine whether boric acid (BA) has a protective effect against brain damage induced by AlCl( 3). For this aim, Sprague-Dawley rats were randomly separated into eight groups: (1) control, (2) AlCl(3) (5 mg/kg/day), (3, 4 and 5) BA (3.25, 36 and 58.5 mg/kg/day), (6, 7 and 8) AlCl(3) (5 mg/kg/day) plus BA (3.25, 36 and 58.5 mg/kg/day). After the animals were killed, the total numbers of neuron in the brain of all groups were determined using an unbiased stereological analysis. In addition to the stereological analysis, all brains were examined histopathologically by using light and electron microscopy. The stereological and histopathological results indicated a high damage of the rat brain tissues in the AlCl(3) and AlCl(3) + high dose BA (36 and 58.5) treatment groups. However, protective effects on neuron were observed in the AlCl(3) + low dose BA (3.25) group when compared other AlCl(3) groups. Our stereological and histopathological findings show that low-dose BA, as a proteasome inhibitor, can decrease the adverse effects of AlCl(3) on the cerebral cortex. PMID:21543463

  19. Electrical, dielectric and electrochemical measurements of bulk aluminum phthalocyanine chloride (AlPcCl)

    NASA Astrophysics Data System (ADS)

    Soliman, I. M.; El-Nahass, M. M.; Mansour, Y.

    2016-01-01

    AC conductivity and the related dielectric properties of bulk aluminum phthalocyanine chloride (AlPcCl) have been studied over a temperature range (303-403 K) and frequency range (42-106 Hz). The universal power law σac (ω)=Aωs has been used to investigate dependence of AC conductivity on frequency. The variation of the frequency exponent (s) with temperature was analyzed in terms of different conduction mechanisms; the predominant conduction mechanism was found to be the correlated barrier hopping (CBH) model. The barrier height was calculated by using (CBH) model, it was found to be 1.41 eV. Dependence of σac (ω) on temperature refers to a linear increase with increasing temperature at different frequencies. The density of states N (EF) was calculated to be equal 4.11×1019 cm-3 using Elliott model. It has been found that AC activation energy decreases with increasing frequency. Dielectric values were analyzed using complex permittivity and complex electric modulus for bulk AlPcCl at different temperatures. The obtained value of HOMO-LUMO energy gap was found to be 1.48 eV.

  20. Morphological and functional state of major salivary glands under conditions of aluminum chloride excess in drinking water.

    PubMed

    Denisov, A B

    2009-12-01

    Morphology and function of the major salivary glands were studied in 50 albino rats drinking water supplemented with aluminum chloride for 2 weeks. Against the background of normal gland appearance, the salivation function and the composition of the saliva were changed: the concentrations of sodium and calcium ions and α-amylase activity were reduced. In parallel, cholesterol content was increased by 54%. PMID:21116512

  1. Reaction of 1-chloro-1-methylcyclohexane with phenyl- and benzyl-trimethylsilanes in the presence of aluminum chloride

    SciTech Connect

    Bolestova, G.I.; Parnes, Z.N.; Vol'pin, M.E.

    1988-10-20

    In the reaction of 1-chloro-1-methylcyclohexane with phenyltrimethylsilane and benzyltrimethylsilane in the presence of aluminum chloride the chlorine atom is substituted by a phenyl or benzyl group with the formation of 1-methyl-1-phenyl- and 1-methyl-1-benzylcyclohexane, respectively. In the case of benzyltrimethylsilane the products from alkylation of the benzene ring of the benzyltrimethylsilane by the 1-methylcyclohexyl carbocation in the Friedel-Crafts reaction are formed in addition to 1-methyl-1-benzylcyclohexane.

  2. [sup 31]P and [sup 27]Al NMR investigations of highly acidic, aqueous solutions containing aluminum and phosphorus

    SciTech Connect

    Mortlock, R.F.; Bell, A.T.; Radke, C.J. Univ. of California, Berkeley )

    1993-01-21

    [sup 31]P and [sup 27]Al NMR spectroscopies have been used to characterize acidic, aqueous solutions of orthophosphoric acid, aluminum chloride, and tetramethylammonium (TMA) hydroxide. The final compositions of the solutions range from 0.1 to 1 mol % P, 0.0 to 20 mol % HCl, P/Al = 0.1 to 20, and P/(TMA)[sub 2]O = 2 to 20. Soluble aluminophosphate cations form reactions of hexaaqua Al monomeric cations, [Al(H[sub 2]O)[sub 6

  3. Study of aluminum corrosion in aluminum solar heat collectors using aqueous glycol solution for heat transfer. Semiannual technical progress report, July 30, 1979-January 31, 1980

    SciTech Connect

    Wong, D.; Cocks, F.H.; Giner, J.

    1980-02-01

    The present work is addressed primarily to the study of the effects of glycol aging at elevated temperatures (above 100/sup 0/C). Glycols are known to be susceptible to thermal decomposition producing new product species which may be aggressive to aluminum. In addition, the possible breakdown of corrosion inhibitors due to long term exposure to high temperature are also investigated. Both uninhibited and inhibited ethylene (as well as propylene) glycols have been aged at temperatures up to 190/sup 0/C for over 2000 h continuously to date. Aliquot samples of each glycol solution tested in this program were taken at 1000 and 2000 h of exposure for chemical analysis and pH measurement. Based on the data obtained so far, solution pH was found to decrease steadily with exposure time. The critical pitting potential of 1100 series aluminum in a 50 vol % aqueous ethylene glycol solution is reported as functions of both temperature and chloride ion concentration. This information is essential in the cathodic protection of pitting corrosion of aluminum.

  4. Effects of chloride ions on electro-coagulation-flotation process with aluminum electrodes for algae removal.

    PubMed

    Gao, Shanshan; Du, Maoan; Tian, Jiayu; Yang, Jianyu; Yang, Jixian; Ma, Fang; Nan, Jun

    2010-10-15

    Electro-coagulation-flotation (ECF) is one of the most promising technologies that offers an attractive alternative to conventional coagulation and flotation. In this study, the effectiveness and mechanisms of algae removal by ECF process using aluminum electrodes was investigated in the presence of Cl(-) ions. The results showed that the addition of Cl(-) ions (1.0, 3.0, 5.0 and 8.0 mM) had a promoting effect on the algae removal in terms of both the cell density and chlorophyll-a, which could be attributed to the following two reasons. Firstly, active chlorine could be generated in the ECF when Cl(-) ions were present. The electrochemically generated active chlorine was demonstrated to be effective for the inactivation of algae cells with the aid of the electric field in the ECF. Secondly, the Cl(-) ions in the algae solution could enhance the release of Al(3+) from the aluminum electrodes in the ECF. Through SEM-EDX analysis, pitting corrosion and alleviated formation of oxide film by Cl(-) ions were observed on the anode surface. When considering that Cl(-) ions are universally present in natural waters, the effects of Cl(-) on ECF process for algae removal are of great significance. PMID:20667652

  5. Effects of liquid aluminum chloride additions to poultry litter on broiler performance, ammonia emissions, soluble phosphorus, total volatile fatty acids, and nitrogen contents of litter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent studies have shown that the use of aluminum sulfate (Al2(SO4)3.14H2O) and aluminum chloride (AlCl3) additions to animal manures are more effective than other chemicals in reducing ammonia (NH3) emissions and phosphorus (P) solubility. Although the use of alum has been intensively used in the ...

  6. A potentiodynamic study of aluminum-lithium alloys in an aqueous sodium chloride environment

    NASA Technical Reports Server (NTRS)

    Tsao, C.-H. T.; Pizzo, P. P.

    1985-01-01

    The characteristics of the potentiodynamic curves for Al-Li alloys in 3.5 percent NaCl aqueous solution are explained and the electrochemical parameters of the potentiodynamic technique are correlated to observed pitting and intergranular cracking behavior. It is shown that the oxygen content of the sodium chloride electrolyte plays an important role in the electrochemical behavior of Al-Li alloys. The potentiodynamic behavior of the alloys is found to be insensitive to variation in compositional content and heat treatment, both of which affect the stress-corrosion behavior. Stringer oxide particle attack and random pitting are observed. It is shown that alternate-immersion exposure prior to potentiodynamic polarization may offer a means of assessing susceptibility to stress-corrosion cracking.

  7. Solution-Derived, Chloride-Containing Minerals as a Waste Form for Alkali Chlorides

    SciTech Connect

    Riley, Brian J.; Crum, Jarrod V.; Matyas, Josef; McCloy, John S.; Lepry, William C.

    2012-10-01

    Sodalite [Na8(AlSiO4)6Cl2] and cancrinite [(Na,K)6Ca2Al6Si6O24Cl4] are environmentally stable, chloride-containing minerals and are a logical waste form option for the mixed alkali chloride salt waste stream that is generated from a proposed electrochemical separations process during nuclear fuel reprocessing. Due to the volatility of chloride salts at moderate temperatures, the ideal processing route for these salts is a low-temperature approach such as the sol-gel process. The sodalite structure can be easily synthesized by the sol-gel process; however, it is produced in the form of a fine powder with particle sizes on the order of 1–10 µm. Due to the small particle size, these powders require additional treatment to form a monolith. In this study, the sol-gel powders were pressed into pellets and fired to achieve > 90% of theoretical density. The cancrinite structure, identified as the best candidate mineral form in terms of waste loading capacity, was only produced on a limited basis following the sol-gel process and converted to sodalite upon firing. Here we discuss the sol-gel process specifics, chemical durability of select waste forms, and the steps taken to maximize chloride-containing phases, decrease chloride loss during pellet firing, and increase pellet densities.

  8. Chloride content of Rocky Flats scrub alloy eleventh campaign solution following head end treatment

    SciTech Connect

    Holcomb, H.P.

    1988-06-30

    A single batch of dissolver solution from the eleventh Rocky Flats Scrub Alloy (RFSA) campaign has been analyzed for chloride content following head end treatment to reduce its concentration. Scrub alloy buttons were dissolved in Tank 6.4D during May. In subsequent head end processing, chloride was precipitated with mercurous ion added as the nitrate. The precipitate, Hg{sub 2}Cl{sub 2}, was concurrently removed with the gelatin floc via centrifugation. Duplicate samples from Tank 11.2, containing the head end product, produced excellent agreement between their density measurements, acid analyses, and gross alpha activities, indicating them to be truly representative of the tank`s contents. Duplicate aliquots from each of these solutions were analyzed using the turbidimetric chloride method developed in the Separations Technology Laboratory. These resulted in an average chloride value of 41 ppm ({micro}g/mL) chloride for the head end product. Relative standard deviation of the measurement was {+-}4 ppm (n = 4), a precision of {+-}10%. Such a variance is normal at this low chloride level. Since initial chloride values prior to head end averaged 1455 ppm (0.041M), as analyzed by Laboratories Department, a chloride DF of approximately 35 was obtained. Such a reduced chloride level (to less than 100 ppm) in the treated solution will permit further canyon processing with minimal corrosion.

  9. Copper extraction from chloride solutions with mixtures of solvating and chelating reagents

    SciTech Connect

    Borowiak-Resterna, A.; Szymanowski, J.

    2000-01-01

    Equimolar mixtures of N,N,N{prime},N{prime}-tetrahexylpyridine-3,5-dicarboxamide (L) with 2-hydroxy-5-t-octylbenzophenone oxime or 1-phenyldecane-1,3-dione (HB), were used to extract copper from chloride solutions of various concentration of chloride ions. Chloride ions were then scrubbed out with water or ammoniacal solutions and copper was transferred from the solvate CuCl{sub 2}L{sub 2} to chelate CuB{sub 2}. Both studied systems permit effective extraction of copper and removal of chloride ions from the organic phase. Some protonation of solvating reagent L occurs, however, when copper is stripped from the chelate with hydroxyoxime. This negative effect can be suppressed when 1-phenyldecane-1,3-dione is used as a chelating agent. The scrubbing of chloride ions must be then carried out with ammoniacal solutions to avoid simultaneous stripping of copper.

  10. Electrochemical, galvanic, and mechanical responses of grade 2 titanium in 6% sodium chloride solution

    SciTech Connect

    Wang, Z.F.; Briant, C.L.; Kumar, K.S.

    1999-02-01

    The electrochemical, galvanic, and mechanical responses of grade 2 titanium in 6% sodium chloride (NaCl) solution at different temperatures were investigated. The initial corrosion potential and cathodic reaction rate increased with decreasing pH and increasing temperature. The initial corrosion potential changed when titanium was coupled with other metals. Naval brass and alloy 600 (UNS N06600) anodically polarized titanium, while zinc and aluminum caused titanium to become a cathode. HY80 steel (UNS K31820), type 316 stainless steel ([SS] UNS S31600), and Monel K500 (UNS N05500, a copper-nickel alloy), polarized titanium anodically or cathodically depending upon temperature and pH. Hydrides formed on the titanium surface at potentials < {approximately} {minus}600 mV{sub SCE} to {minus}700 mV{sub SCE}. Zinc at all temperatures and HY80 at high temperatures caused hydride formation in titanium when coupled galvanically with titanium. Mechanical tests showed an {approx} 10% decrease in ductility under prior and dynamic hydrogen charging conditions.

  11. Doping effect of human blood on surface microstructure of cupric chloride dendrites grown from aqueous solutions

    NASA Astrophysics Data System (ADS)

    Shibata, Takashi; Takakuwa, Yuichi; Tanaka, Akemi; Iguchi, Tomiko; Kogure, Mitsuko; Ogawa, Tomoya

    1996-10-01

    Surface microstructures of cupric chloride dendrites grown in aqueous solutions without and with doping of blood obtained from healthy individuals showed remarkable differences when studied by atomic force microscopy.

  12. Evaluation of aluminum indices to predict aluminum toxicity to plants grown in nutrient solutions

    SciTech Connect

    Alva, A.K.; Blamey, F.P.C.; Edwards, D.G.; Asher, C.J.

    1986-01-01

    Difficulty has been experienced in establishing a suitable aluminum (Al) index to predict Al toxicity to plants grown in nutrient solutions with a wide range of properties. In the present study, relationships were evaluated between root length and (i) concentration of total Al, (ii) concentration of monomeric Al, and (iii) the sum of the activities of monomeric Al species (..sigma..a/sub Al mono/) in solution. Results are reported for soybean (Glycine max (L.) Merr.), subterranean clover (Trifolium subterraneum L.), alfalfa (Medicago sativa L.), and sunflower (Helianthus annuus L.). Total Al concentration in solution, comprising polymeric and monomeric Al species, was a poor index of Al toxicity, confirming the hypothesis that only monomeric Al is toxic to root growth. In solutions with widely differing composition, the concentration of monomeric Al also proved unsatisfactory due to ionic strength effects on the activities of monomeric Al species. ..sigma..a/sub Al mono/ was the best index of Al toxicity, accounting for 72 to 92% of the variation in root length depending on the plant species. Root length was reduced by 50% at ..sigma..a/sub Al mono/ of 7-16 ..mu..M in soybean, 13 ..mu..M in subterranean clover and alfalfa, and 11 ..mu..M in sunflower.

  13. Memory recuperative potential of rifampicin in aluminum chloride-induced dementia: role of pregnane X receptors.

    PubMed

    Kaur, P; Sodhi, R K

    2015-03-12

    The present study has been designed to investigate the potential of rifampicin [Pregnane X receptors (PXR) agonist] in experimental dementia. Aluminum chloride (AlCl3) [100mg/kg, p.o. for 42days] was administered to Wistar rats (n=6) to induce dementia. Morris water maze (MWM) test was used to assess learning and memory and rota rod test was used to assess locomotor activity of the animals. A battery of biochemical tests and histopathological evaluation using hematoxylin and eosin (H&E) and Congo Red stains were performed at the end of the study. AlCl3-treated rats demonstrated impaired cognition and locomotor activity on MWM apparatus and rota rod test, respectively. These animals exhibited a significant rise in acetylcholinesterase (AChE) activity (138±3.6), thiobarbituric acid reactive species (TBARS) level (15±1.6), nitrite (56±2.4) level and myeloperoxidase (MPO) activity (4.1±0.9) along with decline in reduced glutathione (GSH) level (22±1.3) in comparison to the control group (p<0.05). Further the H&E and Congo Red-stained cerebral cortex sections of AlCl3-treated rats indicated severe neutrophilic infiltration and amyloid deposition. Rifampicin-treated AlCl3-rats exhibited significant attenuation in memory deficits, biochemical parameters like AChE activity (33±1.4), TBARS level (4.1±1.0), nitrite level (64±2.6), MPO activity (3.6±1.0) and GSH level (53±2.4) along with improved histopathological alterations and locomotor activity when compared with AlCl3-treated rats (p<0.05). Combined administration of ketoconazole (a PXR antagonist) and rifampicin to AlCl3-treated animals reversed the rifampicin-induced protective effects. Therefore the results obtained from the study indicate a defensive role of rifampicin in memory dysfunction which may probably be due to its anti-cholinesterase, anti-oxidative, anti-inflammatory and amyloid lowering effects. Moreover the study speculates the potential of PXR in the pathophysiology of dementia which is subject

  14. Chemical characterization of a potassium hydroxyapatite prepared by soaking in potassium chloride and carbonate solutions.

    PubMed

    Nordström, E G; Karlsson, K H

    1992-01-01

    A potassium-doped synthetic apatite was prepared by soaking hydroxyapatite in potassium carbonate and potassium chloride solutions. The hydroxyapatite was prepared by firing slip cast ceramic bodies in vacuum at 1100 degrees C. The conical ceramic samples and a crushed material of this were soaked in carbonate and chloride solutions for 2, 4, 6, and 8 weeks. Potassium, calcium, and phosphate were determined by direct current plasma emission spectroscopy. The carbonate content was determined by thermogravimetric analysis and chloride titrimetrically. After 2 weeks, one potassium ion substituted one calcium ion when soaked in a carbonate solution. When soaked in the chloride solution substitution occurred to the same extent. At phosphate sites the substitution of phosphate for carbonate occurred at one sixth of the sites after 2 weeks. Chloride incorporated one half of the OH-sites after 2 weeks. After 4 weeks about one chloride ion was found in the apatite, and after 6 weeks one and a half of the OH-sites were occupied by chloride ions. PMID:1483120

  15. Orthophosphate and metaphosphate ion removal from aqueous solution using alum and aluminum hydroxide.

    PubMed

    Georgantas, D A; Grigoropoulou, H P

    2007-11-01

    The removal of orthophosphates (10(-2) kg P m(-3)), condensed phosphates (10(-2) kg P m(-3)), and mixtures of both (5 x 10(-3) kg P m(-3) as orthophosphate and 5 x 10(-3) kg P m(-3) as metaphosphate) in aqueous solution is studied using alum and aluminum hydroxide. The effects of coagulant dose, pH, temperature, aging of aluminum hydroxide, and presence of different ions are investigated. On the basis of the experimental results, alum is much more efficient in phosphorus removal than aluminum hydroxide even if, in both cases, at the conditions studied, the active coagulant form is Al(OH)(3). The differences then could be due to the higher activity of the in situ formed hydroxide. Orthophosphates and metaphosphates seem to have similar behavior vs pH variation: maximum removal is achieved at pH values 5-6 in all cases. On the other hand, in the simultaneous presence of both P forms, orthophosphate and metaphosphate ions have different affinities for the surface sites of aluminum hydroxide, since for both alum and aluminum hydroxide, orthophosphates are preferentially removed compared to metaphosphates, due probably to orientation effects and the charge per P atom. The presence of sodium, potassium, magnesium, sulfate, chloride, and magnesium, at the concentrations studied and for a pH value of 6, does not influence P removal. Temperature variation, between 25 and 60 degrees C, does not affect alum efficiency but both P forms are increasingly removed with increasing temperature, probably due to polymer Al(OH)(3) breaking, producing new surfaces for adsorption. Aging decreases sorption capacity of Al(OH)(3), while crystallites of increasing size are formed. Finally adsorption of both P forms is best described by the Freundlich isotherm [[K(F)=(49.1-69.1) x 10(-3) (m(3)kg(-1))(1/N), 1/N: 0.14-0.19 for T=25-60 degrees C] and [ K(F)=(1.58-2.79) x 10(-3) (m(3)kg(-1))(1/N), 1/N: 2.17-2.47 for T=25-60 degrees C] for orthophosphate and metaphosphate, respectively. PMID

  16. Aluminum uptake and inhibition of enamel dissolution by sequential treatments with aluminum solutions.

    PubMed

    Kleber, C J; Putt, M S

    1994-01-01

    The effects of sequentially applied solutions containing aluminum (Al) on enamel uptake and inhibition of acid dissolution were investigated. Following 10 consecutive 5-min treatments with seven Al solutions varying in concentration from 0.15 to 2.0 mmol/l, the subsequent acid dissolution of enamel was progressively reduced from 0 to over 70%. Teeth treated with 1.5 mmol/l Al from 1 to 30 consecutive 5-min periods demonstrated a stepwise increase in the reduction of enamel acid dissolution ranging from about 10 to 90%. Following the same treatment regimen, the amount of Al deposited in the enamel varied from 2,500 ppm after a single 5-min application to approximately 9,000 ppm after 20 or 30 consecutive treatments. These experiments showed that teeth repeatedly exposed to low concentrations of Al solutions (i.e. < 2 mmol/l) progressively accumulated significant amounts of Al in the surface enamel, which was associated with a concomitant decrease in the acid dissolution rate of enamel. PMID:7850841

  17. Process for producing gallium-containing solution from the aluminum smelting dust

    SciTech Connect

    Era, A.; Matsui, S.; Ikeda, H.

    1988-03-01

    A process is described for producing a gallium-containing solution from aluminum smelting dust comprising leaching aluminum smelting dust with a mineral acid selected from the group consisting of sulfuric acid, hydrochloric acid and nitric acid, and adding an oxidizing agent to the aluminum smelting dust at the time of leaching to preferentially leach and extract gallium from the aluminum smelting dust without extracting aluminum from the aluminum smelting dust. The oxidizing agent is selected from the group consisting of potassium permanganate, manganese dioxide, hydrogen peroxide, ozone, potassium chromate, potassium dichromate, ammonium persulfate, sodium hydrochlorite, sodium chlorite and sodium chlorate. The leached aluminum smelting dust is filtered to obtain a gallium-containing solution of dissolved gallium.

  18. Effect of Lead Chloride on the Growth and Surface Properties of Potassium Chloride Crystals from Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Podder, Jiban; Evitts, Richard William; Besant, Robert William

    2014-05-01

    Pure potassium chloride (KCl) and lead chloride (PbCl2)-doped KCl crystals were grown from saturated aqueous solutions by a solvent evaporation process. The effects of Pb2+ on the surface morphology, structural and mechanical properties of KCl crystal were investigated. The surface morphology of the cubic structured crystals was studied by scanning electron microscopy (SEM), X-ray diffraction and the elemental mappings at the microstructural level were determined by energy dispersive X-ray (EDX) spectroscopy. The mass growth rate was found to decrease when the Pb2+ ions were present and the volume growth flux was also found to decrease with time and initial concentration of impurity. A Vickers micro-hardness study shows that Pb-doped KCl crystals are harder than pure KCl crystals.

  19. Formation of linear polyenes in poly(vinyl alcohol) films catalyzed by phosphotungstic acid, aluminum chloride, and hydrochloric acid

    NASA Astrophysics Data System (ADS)

    Tretinnikov, O. N.; Sushko, N. I.; Malyi, A. B.

    2016-07-01

    Formation of linear polyenes-(CH=CH)n-via acid-catalyzed thermal dehydration of polyvinyl alcohol in 9- to 40-µm-thick films of this polymer containing hydrochloric acid, aluminum chloride, and phosphotungstic acid as dehydration catalysts was studied by electronic absorption spectroscopy. The concentration of long-chain ( n ≥ 8) polyenes in films containing phosphotungstic acid is found to monotonically increase with the duration of thermal treatment of films, although the kinetics of this process is independent of film thickness. In films containing hydrochloric acid and aluminum chloride, the formation rate of polyenes with n ≥ 8 rapidly drops as film thickness decreases and the annealing time increases. As a result, at a film thickness of less than 10-12 µm, long-chain polyenes are not formed at all in these films no matter how long thermal duration is. The reason for this behavior is that hydrochloric acid catalyzing polymer dehydration in these films evaporates from the films during thermal treatment, the evaporation rate inversely depending on film thickness.

  20. Role of lipid composition and lipid peroxidation in the sensitivity of fungal plant pathogens to aluminum chloride and sodium metabisulfite.

    PubMed

    Avis, Tyler J; Michaud, Mélanie; Tweddell, Russell J

    2007-05-01

    Aluminum chloride and sodium metabisulfite have shown high efficacy at low doses in controlling postharvest pathogens on potato tubers. Direct effects of these two salts included the loss of cell membrane integrity in exposed pathogens. In this work, four fungal potato pathogens were studied in order to elucidate the role of membrane lipids and lipid peroxidation in the relative sensitivity of microorganisms exposed to these salts. Inhibition of mycelial growth in these fungi varied considerably and revealed sensitivity groups within the tested fungi. Analysis of fatty acids in these fungi demonstrated that sensitivity was related to high intrinsic fatty acid unsaturation. When exposed to the antifungal salts, sensitive fungi demonstrated a loss of fatty acid unsaturation, which was accompanied by an elevation in malondialdehyde content (a biochemical marker of lipid peroxidation). Our data suggest that aluminum chloride and sodium metabisulfite could induce lipid peroxidation in sensitive fungi, which may promote the ensuing loss of integrity in the plasma membrane. This direct effect on fungal membranes may contribute, at least in part, to the observed antimicrobial effects of these two salts. PMID:17337539

  1. Speciation of aluminum in aqueous solutions using ion chromatography.

    PubMed

    Bertsch, P M; Anderson, M A

    1989-03-15

    An ion chromatographic method in which aluminum (AI) is quantitatively determined via postcolumn derivatization with Tiron (4,5-dihydroxy-m-benzenedisulfonic acid) was evaluated for its utility as a method for speciating AI in aqueous solutions. Fluro-, oxalato-, and citratoaluminum complexes were identified by distinct peaks within chromatograms of AI solutions when the appropriate ligand was added. Excellent quantitative agreement between predicted species concentrations (via the thermodynamic speciation model GEOCHEM) and those determined by ion chromatography was obtained for samples prepared in the eluent matrix. The predominantly outer sphere sulfatoaluminum complexes were not observed to elute as singly charged species, but rather exhibited a retention time indistinguishable from the AI(H2O)6(3+) species. It is concluded that inner sphere AI complexes (generally possessing relatively high association constants) possess adequate kinetic stability to withstand degradation during the ion exchange process, whereas outer sphere complexes apparently readily dissociate in the presence of the sulfonate exchange sites. Deviations in sample ionic strength (mu) and pH from that of the eluent resulted in some redistribution among species, the degree of which was ligand specific. PMID:2729589

  2. Water and solute transfer between a prairie wetland and adjacent uplands, 2. Chloride cycle

    NASA Astrophysics Data System (ADS)

    Hayashi, Masaki; van der Kamp, Garth; Rudolph, Dave L.

    1998-06-01

    The quality of water in lakes and wetlands depends on the exchange of solutes with adjacent uplands. In many prairie wetlands, the input of water is dominated by snowmelt runoff and the outputis dominated by groundwater flow. We use chloride as a tracer to quantify the mass transfer processes associated with surface runoff and groundwater flow between a wetland in Saskatchewan, Canada and the surrounding upland. Snowmelt runoff transports 4-5 kg yr -1 of chloride from the upland to the wetland. Most of this chloride infiltrates under the wetland and moves laterally to the upland with shallow groundwater. Under the upland, chloride moves upward in the vadose zone with soil water, and accumulates near the surface as water is consumed by evapotranspiration. Part of this chloride mixes with snowmelt runoff and moves back to the wetland Therefore, chloride is cycled between the wetland and the upland at an approximate rate of 5 kg yr -1. The chloride cycle occurs within 5-6 m of the ground surface. A small amount of chloride escapes from the cycle with the downward flow of groundwater into the deep aquifer. The estimated flux of chloride leaving the cycle is 0.1-0.6 kg yr -1, which is of the same order of magnitude as the rate at which the catchment receives atmospheric deposition of chloride. Because the atmospheric input is reasonably well known over the prairie region, the concentration of chloride in groundwater under recharge wetlands can be used to estimate the recharge rate of deep aquifers.

  3. Effect of aluminum chloride hemostatic agent on microleakage of class V composite resin restorations bonded with all-in-one adhesive

    PubMed Central

    Mohammadi, Narmin; Bahari, Mahmood; Pournaghi-Azar, Fatemeh; Mozafari, Aysan

    2012-01-01

    Objectives: Since hemostatic agents can induce changes on enamel and dentin surfaces and influence composite resin adhesion, the aim of the present study was to evaluate the effect of the aluminum chloride hemostatic agent on the gingival margin microleakage of class V (Cl V) composite resin restorations bonded with all-in-one adhesive. Study design: Cl V cavities were prepared on the buccal surfaces of 60 sound bovine permanent incisors. Gingival margins of the cavities were placed 1.5 mm apical to the cemento-enamel junction (CEJ). The teeth were randomly divided into two groups of 30. In group 1, the cavities were restored without the application of a hemostatic agent; in group 2, the cavities were restored after the application of the hemostatic agent. In both groups all-in-one adhesive and Z250 composite resin were used to restore the cavities with the incremental technique. After finishing and polishing, the samples underwent a thermocycling procedure, followed by immersion in 2% basic fuschin solution for 24 hours. The samples were sectioned and gingival microleakage was evaluated under a stereomicroscope. The non-parametric Mann-Whitney U test was used to compare microleakage between the two groups. Statistical significance was defined at P<0.05. Results: A statistically significant difference was observed in microleakage between the two groups (P<0.001). Conclusions: Contamination of Cl V composite resin restorations bonded with all-in-one adhesive with aluminum chloride hemostatic agent significantly increases restoration gingival margin microleakage. Key words:All-in-one adhesive resin, composite resin restoration, hemostatic agent, microleakage. PMID:22322497

  4. Confinement-induced vitrification of aqueous sodium chloride solutions

    NASA Astrophysics Data System (ADS)

    Zhao, Lishan; Pan, Liqing; Cao, Zexian; Wang, Qiang

    2016-03-01

    Bulk aqueous solution of NaCl is a poor glass former, it vitrifies only under high pressure. Here we report the investigation of glass transition of NaCl solutions confined in nanopores. By inspecting the dependence of glass transition temperature and heat flow jump at transition it is concluded that vitrification of confined NaCl solutions involves only the eutectic phase and the precipitated ice core may help furnish the demanded confinement strength. Ion-water interaction still plays a dominant role in determining vitrification of solutions even under nano-confinement, as under exactly the same confinement conditions vitrification of aqueous KCl solutions was not detected.

  5. Electrical conductivity of aqueous solutions of aluminum salts

    NASA Astrophysics Data System (ADS)

    Vila, J.; Rilo, E.; Segade, L.; Cabeza, O.; Varela, L. M.

    2005-03-01

    We present experimental measurements of the specific electrical conductivity (σ) in aqueous solutions of aluminum salts at different temperatures, covering all salt concentrations from saturation to infinite dilution. The salts employed were AlCl3 , AlBr3 , AlI3 , and Al(NO3)3 , which present a 1:3 relationship between the electrical charges of anion and cation. In addition, we have measured the density in all ranges of concentrations of the four aqueous electrolyte solutions at 298.15K . The measured densities show an almost linear behavior with concentration, and we have fitted it to a second order polynomial with very high degree of approximation. The measurement of the specific conductivity at constant temperature reveals the existence of maxima in the conductivity vs concentration curves at molar concentrations around 1.5M for the three halide solutions studied, and at approximately 2M for the nitrate. We present a theoretical foundation for the existence of these maxima, based on the classical Debye-Hückel-Onsager hydrodynamic mean-field framework for electrical transport and its high concentration extensions, and also a brief consideration of ionic frictional coefficients using mode-coupling theory. We also found that the calculated values of the equivalent conductance vary in an approximately linear way with the square root of the concentration at concentrations as high as those where the maximum of σ appears. Finally, and for completeness, we have measured the temperature dependence of the electrical conductivity at selected concentrations from 283to353K , and performed a fit to an exponential equation of the Vogel-Fulcher-Tamman type. The values of the calculated temperatures of null mobility of the four salts are reported.

  6. Recovery of chromium from spent plating solutions by a chromyl chloride process

    SciTech Connect

    Guddati, S.L.; Holsen, T.M.; Selman, J.R.

    1994-12-31

    A novel chromyl chloride process has been investigated for the recovery of hexavalent chromium from spent plating solutions. In this process chromium is converted to chromyl chloride by reacting it with concentrated hydrochloric acid and then separated as a heavy underlayer, or alternatively, extracted into a solvent as follows: H{sub 2}CrO{sub 4} + 2 HCl {Leftrightarrow} CrO{sub 2}Cl{sub 2} + 2 H{sub 2}O. Purified chromyl chloride is then hydrolyzed and the resulting solution dried and chromium trioxide recovered. H{sub 2}CrO{sub 4} [+ 2 HCl] {Leftrightarrow} CrO{sub 3}{down_arrow} + H{sub 2}O{up_arrow} [+ 2 HCl{up_arrow}]. In preliminary experiments more than 98% of the chromium has been separated as chromyl chloride (without using any solvent) from an aqueous solution which originally contained 200 g/L chromic acid. Temperature and reactant concentrations were found to greatly affect the stability and the yield of chromyl chloride respectively. Equilibrium conditions have been identified using a geochemical equilibrium speciation model. A statistical analysis of experimental results has been performed to quantify the effects of various parameters on the yield of chromyl chloride.

  7. Aluminum chloride induced oxidative damage on cells derived from hippocampus and cortex of ICR mice.

    PubMed

    Rui, Ding; Yongjian, Yang

    2010-04-01

    Aluminum (Al) is among the most abundant elements on earth, it has been associated with the etiology of Alzheimer's disease. In the present study, AlCl(3) was administered with the dose of 10, 50 or 300 mg/kg b.wt/day through diet for 100 days. On day 101, overnight-fasted animals were sacrificed, the whole brains were removed and the cells from hippocampus or cortex were separated for the measurements: malondialdehyde (MDA), superoxide dismutase (SOD), nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) damage. AlCl(3) exposure resulted in increased MDA levels accompanied by decreased activities of SOD in the cells. Comet assay demonstrated that aluminum induces nDNA damage in a dose-dependent manner, dramatically increased formation of 8-hydroxy 2-deoxyguanosine (8-OHdG) in the mtDNA isolated from the cells was also measured. The alterations seem more serious than the results displayed by the studies performed with lower doses of aluminum. However, a detailed biochemical mechanism by which aluminum accelerates mtDNA damage has not yet been identified, but the decrease in superoxide dismutase (SOD) activity and increase in MDA level in aluminum-treated mice may suggest the involvement of oxidative stress. PMID:20156420

  8. Redox flow batteries based on supporting solutions containing chloride

    SciTech Connect

    Li, Liyu; Kim, Soowhan; Yang, Zhenguo; Wang, Wei; Nie, Zimin; Chen, Baowei; Zhang, Jianlu; Xia, Guanguang

    2015-09-01

    Redox flow battery systems having a supporting solution that contains Cl.sup.- ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO.sub.4.sup.2- and Cl.sup.- ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V.sup.2+ and V.sup.3+ in a supporting solution and a catholyte having V.sup.4+ and V.sup.5+ in a supporting solution. The supporting solution can contain Cl.sup.- ions or a mixture of SO.sub.4.sup.2- and Cl.sup.- ions.

  9. Redox flow batteries based on supporting solutions containing chloride

    SciTech Connect

    Li, Liyu; Kim, Soowhan; Yang, Zhenguo; Wang, Wei; Nie, Zimin; Chen, Baowei; Zhang, Jianlu; Xia, Guanguang

    2015-07-07

    Redox flow battery systems having a supporting solution that contains Cl.sup.- ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO.sub.4.sup.2- and Cl.sup.- ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V.sup.2+ and V.sup.3+ in a supporting solution and a catholyte having V.sup.4+ and V.sup.5+ in a supporting solution. The supporting solution can contain Cl.sup.- ions or a mixture of SO.sub.4.sup.2- and Cl.sup.- ions.

  10. Redox flow batteries based on supporting solutions containing chloride

    DOEpatents

    Li, Liyu; Kim, Soowhan; Yang, Zhenguo; Wang, Wei; Zhang, Jianlu; Chen, Baowei; Nie, Zimin; Xia, Guanguang

    2014-01-14

    Redox flow battery systems having a supporting solution that contains Cl.sup.- ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO.sub.4.sup.2- and Cl.sup.- ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V.sup.2+ and V.sup.3+ in a supporting solution and a catholyte having V.sup.4+ and V.sup.5+ in a supporting solution. The supporting solution can contain Cl.sup.- ions or a mixture of SO.sub.4.sup.2- and Cl.sup.- ions.

  11. Investigation of the electrodialysis of an aqueous solution of tin(IV) chloride

    SciTech Connect

    Sharygin, L.M.; Zlokazova, E.I.; Shtin, A.P.

    1987-09-20

    The sol-gel method for the synthesis of sorbents on the basis of oxides of polyvalent metals calls for an investigation of the methods for obtaining aqueous sols of oxides of these metals. The purpose of this work was to investigate the polarization of an anion-exchange membrane in solutions of stannic chloride with different concentrations and during electrodialysis, as well as the current efficiency with respect to chlorine, and the transport numbers of the chloride ion as a function of the current density and the temperature. The polarization curves recorded for an MA-41L membrane in dilute solutions of tin(IV) chloride tended to show an increase in the limiting current in comparison to the case of hydrochloric acid with the same electrical conductivity owing to the ion-exchange properties of the colloidal particles of hydrated tin dioxide formed during the hydrolysis and polymerization of tin in solution.

  12. Control and monitoring of the localized corrosion of zirconium in acidic chloride solutions

    SciTech Connect

    Fahey, J.; Holmes, D.; Yau, T.L.

    1995-09-01

    Zirconium in acidic chloride solutions which are contaminated with ferric or cupric cations is prone to localized corrosion. This tendency can be reduced by ensuring that the zirconium surface is clean and smooth. In this paper, the effect of surface condition on the localized corrosion of zirconium in acidic chloride solutions is predicted with potentiodynamic scans. These predictions are confirmed by weight loss tests on various combinations of surface finish and acid concentrations. A real time indication of localized corrosion is seen by monitoring the electrochemical noise produced between two similar electrodes immersed in an acidic chloride solutions. Electrochemical noise monitoring correlates well with the predictions from potentiodynamic and weight loss experiments. The electrochemical noise results show that while an elevated (more anodic) potential caused by ferric ion contamination may be a necessary condition for localized corrosion, it is not a sufficient condition: A smooth, clean zirconium surface reduces the localized corrosion of zirconium.

  13. LOW TEMPERATURE PROCESS FOR THE REMOVAL AND RECOVERY OF CHLORIDES AND NITRATES FROM AQUEOUS NITRATE SOLUTIONS

    DOEpatents

    Savolainen, J.E.

    1963-01-29

    A method is described for reducing the chloride content of a solution derived from the dissolution of a stainless steel clad nuclear fuel element with an aqua regia dissolution medium. The solutlon is adjusted to a nitric acid concentration in the range 5 to 10 M and is countercurrently contacted at room temperature with a gaseous oxide of nitrogen selected from NO, NO/sub 2/, N/sub 2/ O/sub 3/, and N/sub 2/O/sub 4/. Chlo ride is recovered from the contacted solution as nitrosyl chloride. After reduction of the chloride content, the solution is then contacted with gaseous NO to reduce the nitric acid molarity to a desired level. (AEC)

  14. Fabrication and Performance of All-Solid-State Chloride Sensors in Synthetic Concrete Pore Solutions

    PubMed Central

    Gao, Xiaojian; Zhang, Jian; Yang, Yingzi; Deng, Hongwei

    2010-01-01

    One type of all-solid-state chloride sensor was fabricated using a MnO2 electrode and a Ag/AgCl electrode. The potentiometric response of the sensor to chloride in synthetic concrete pore solutions was systematically studied, and the polarization performance was also evaluated. The results show a good linear relationship between the potential reading of the sensor and the logarithm of chloride activity (concentration ranges from 0.05 to 5.0 M), and the potential value remains stable with increasing immersion time. The existence of K+, Ca2+, Na+ and SO42− ions have little influence on the potentiometric response of the sensor to chloride, but the pH has a significant influence on the potential value of the sensor at low chloride concentration. The potential reading of the sensor increases linearly with the solution temperature over the range from 5 to 45 °C. Meanwhile, an excellent polarization behavior is proven by galvanostatic and potentiodynamic tests. All of the results reveal that the developed sensor has a great potential for monitoring chloride ions in concrete environments. PMID:22163467

  15. Fabrication and performance of all-solid-state chloride sensors in synthetic concrete pore solutions.

    PubMed

    Gao, Xiaojian; Zhang, Jian; Yang, Yingzi; Deng, Hongwei

    2010-01-01

    One type of all-solid-state chloride sensor was fabricated using a MnO(2) electrode and a Ag/AgCl electrode. The potentiometric response of the sensor to chloride in synthetic concrete pore solutions was systematically studied, and the polarization performance was also evaluated. The results show a good linear relationship between the potential reading of the sensor and the logarithm of chloride activity (concentration ranges from 0.05 to 5.0 M), and the potential value remains stable with increasing immersion time. The existence of K(+), Ca(2+), Na(+) and SO(4) (2-) ions have little influence on the potentiometric response of the sensor to chloride, but the pH has a significant influence on the potential value of the sensor at low chloride concentration. The potential reading of the sensor increases linearly with the solution temperature over the range from 5 to 45 °C. Meanwhile, an excellent polarization behavior is proven by galvanostatic and potentiodynamic tests. All of the results reveal that the developed sensor has a great potential for monitoring chloride ions in concrete environments. PMID:22163467

  16. Nucleation and growth of zinc from chloride concentrated solutions

    SciTech Connect

    Trejo, G.; Ortega B, R.; Meas V, Y.; Ozil, P.; Chainet, E.; Nguyen, B.

    1998-12-01

    The electrodeposition of metals is a complex phenomenon influenced by a number of factors that modify the rates of nucleation and growth and determine the properties of the deposits. In this work the authors study the influence of the zinc chloride (ZnCl{sub 2}) concentration on the zinc nucleation process on glassy carbon, in a KCl electrolyte under conditions close to those employed in commercial acid deposition baths for zinc. The electrochemical study was performed using cyclic voltammetry and potentiostatic current-time transients. The charge-transfer coefficient and the formal potential for ZnCl{sub 2} reduction were evaluated from cyclic voltammetry experiments. The nucleation process was analyzed by comparing the transients obtained with the known dimensionless (i/i{sub m}){sup 2} vs. t/t{sub m} response for instantaneous or progressive nucleation. The results show that the nucleation process and the number density of sites are dependent on ZnCl{sub 2} concentration. Scanning electron microscopy analysis of the deposits shows that the deposits are homogeneous and compact although a change in the morphology is observed as a function of ZnCl{sub 2} concentration. Evaluation of the corrosion resistance reveals the influence of the nucleation process on the subsequent corrosion resistance of the zinc deposits.

  17. Flocculation kinetics mechanism and floc formation prepared by poly aluminum chloride coupled with polyacrylamide for ship ballast water.

    PubMed

    Zhou, Zhimin; Liu, Sha; Jia, Linan

    2016-01-01

    The performance of flocculants prepared by poly aluminum chloride (PAC) and polyacrylamide (PAM) on treating ballast water collected at the Dalian new port area, the evaluation depending on the values of reaction parameters, and kinetics mechanism of flocculation were investigated in this study. Accordingly, the flocculants of 0.1 g·L(-1), prepared by mixing PAC of 10% with PAM of 2.0‰, enabled the removal rate of zooplankton and phytoplankton to reach 91% in ballast water at 20 °C. Based on flocculation kinetics mechanism analysis, the efficient vortex size during stirring should be larger than the floc particles, and gradient of fluctuating velocity provide the impetus for turbulence flocculation. The results of this study could be relevant to understanding particle-floc interactions during developmental flocculation, and during application of ballast water treatment. PMID:27386983

  18. Effect of aluminum chloride on formation of a polyconjugated bond system in the initial stage of polyvinyl alcohol thermal decomposition

    NASA Astrophysics Data System (ADS)

    Kulak, A. I.; Bondareva, G. V.; Shchurevich, O. A.

    2013-03-01

    Fine-structure bands have been located in electronic absorption spectra of polyvinyl alcohol (PVA) films decomposed thermally in air at 80-150°C. Doping of the PVA film with aluminum chloride (thermolysis catalyst) was found both to enhance the degree of thermal decomposition and to reduce the starting temperature for formation of poly-π-conjugated chains although it had no effect on the spectral positions of the polyene-unit absorption bands. Values of the band gap of heat-treated PVA films were determined to be in the range 1.65-1.78 eV based on an analysis of the electronic spectra long-wavelength edge.

  19. Effect of natural dissolved organic carbon on phosphate removal by ferric chloride and aluminum sulfate treatment of wetland waters

    NASA Astrophysics Data System (ADS)

    Qualls, Robert G.; Sherwood, Lindsay J.; Richardson, Curtis J.

    2009-09-01

    The use of wetlands for the removal of excess N and P has become widespread. Some sensitive P-limited ecosystems, however, may require additional reductions in the concentration of P entering the system. It has been proposed that the treatment of wetlands through addition of ferric chloride or aluminum sulfate can augment the natural P removal mechanisms. However, high concentrations of natural dissolved organic matter may interfere with the removal of P by metal addition. We evaluated the doses of ferric chloride and aluminum sulfate necessary to reduce total P concentrations below 0.32 μM (10 μg/L) in water from the Northern Everglades, and we determined the effect of various concentrations (21, 38, and 60 mg/L) of natural dissolved organic carbon (DOC) on the removal of PO4 and total P. High concentrations of natural DOC inhibited both the short-term removal of PO4 and the longer-term removal of total P from the water column. Similar results were observed using 15 μM citric acid in an experiment to determine whether citric acid could effectively mimic the inhibition of phosphorus removal associated with natural DOC. Stoichiometry of these experiments indicates that the mechanism of natural DOC interference was not complexation of the metal ions by the DOC; we hypothesize that it could be adsorption to the terminal hydroxyl groups on a polynuclear Fe or Al colloid, effectively blocking the adsorption sites from a phosphate molecule. Also, the ability of citric acid to mimic the inhibitory effects also suggests that the results of the study are broadly applicable to wetland and other waters with high natural organic acid concentrations.

  20. Solute rejection by porous glass membranes. I - Hyperfiltration of sodium chloride and urea feed solutions.

    NASA Technical Reports Server (NTRS)

    Ballou, E. V.; Wydeven, T.; Leban, M. I.

    1971-01-01

    Hyperfiltration of sodium chloride and urea was studied with porous glass membranes in closed-end capillary form, to determine the effect of pressure, temperature, and concentration variations, and lifetime rejection and flux characteristics. Rejection data for sodium chloride were consistent with the functioning of the porous glass as a low-capacity ion-exchange membrane.

  1. Rheology and viscosity scaling of gelatin/1-allyl-3-methylimidazolium chloride solution

    NASA Astrophysics Data System (ADS)

    Qiao, Congde; Li, Tianduo; Zhang, Ling; Yang, Xiaodeng; Xu, Jing

    2014-05-01

    Gelatin/1-allyl-3-methylimidazolium chloride solutions are prepared by using the ionic liquid 1-allyl-3-methylimidazolium chloride as solvent. The rheological properties of the gelatin solutions have been investigated by steady shear and oscillatory shear measurements. In the steady shear measurements, the gelatin solutions with high concentration show a shear-thinning flow behavior at high shear rates, while another shear thinning region can be found in the dilute gelatin solutions at low shear rates. The overlap concentration of gelatin in [amim]Cl is 1.0 wt% and the entanglement concentration is a factor of 4 larger (4.0 wt%). The high intrinsic viscosity (295 mL/g) indicates that the gelatin chains dispersed freely in the ionic liquid and no aggregation phenomenon occurs in dilute gelatin solution. The frequency dependences of modulus changed obviously with an increase in gelatin concentration. The empirical time-temperature superposition principle holds true at the experimental temperatures.

  2. Role of propolis (bee glue) in improving histopathological changes of the kidney of rat treated with aluminum chloride.

    PubMed

    El-Kenawy, Ayman El-meghawry; Hussein Osman, Hosam Eldin; Daghestani, Maha Hasan

    2014-09-01

    Humans are frequently exposed to aluminum from various food additives, therapeutic treatments and the environment, and it can be potentially toxic. This study is aimed to elucidate the protective effects of propolis against aluminum chloride (AlCl3 )-induced histopathological and immunohistochemical changes in kidney tissues of rats. Sixty Wistar Albino male rats (average weight 250-300 g) were divided into three equal groups. The first served as a negative control. The second received AlCl₃ (34 mg/kg bw, 1/ 25 LD 50). The third were administered AlCl₃ (34 mg/kg bw, 1/ 25 LD 50) plus propolis (50 mg/kg bw). Doses were given once daily via a gavage for 8 weeks every day. The results showed that shrunken glomeruli, intraglomerular congestion, loss of apical microvilli, degeneration of mitochondria and widened rough endoplasmic reticulum were also observed in the Proximal Convoluted Tubules of these animals. Treatment with propolis ameliorated the harmful effects of AlCl₃ ; this was also proved histopathologically by the noticeable improvement in the renal tissues. There were also significant variations in the expressed of ki-67 and p53 proteins. It can be concluded that propolis may be promising as a natural therapeutic agent in AlCl₃ -induced renal toxicity and oxidative stress in rat kidneys. PMID:23172825

  3. Electrochemical Evaluation of Stainless Steels in Acidified Sodium Chloride Solutions

    NASA Technical Reports Server (NTRS)

    Calle, L. M.; MacDowell, L. G.; Vinje, R. D.

    2004-01-01

    This paper presents the results of an investigation in which several 300-series stainless steels (SS): AISI S30403 SS (UNS S30403), AISI 316L SS (UNS S31603), and AISI 317L SS (LINS S31703), as well as highly-alloyed: SS 254-SMO (UNS S32154), AL-6XN (N08367) and AL29-4C (UNS S44735), were evaluated using DC electrochemical techniques in three different electrolyte solutions. The solutions consisted of neutral 3.55% NaCl, 3.55% NaCl in 0.1N HCl, and 3.55% NaCl in 1.0N HCl. These solutions were chosen to simulate environments that are less, similar, and more aggressive, respectively, than the conditions at the Space Shuttle launch pads. The electrochemical test results were compared to atmospheric exposure data and evaluated for their ability to predict the long-term corrosion performance of the subject alloys. The electrochemical measurements for the six alloys indicated that the higher-alloyed SS 254-SMO, AL29-4C, and AL-6XN exhibited significantly higher resistance to localized corrosion than the 300-series SS. There was a correlation between the corrosion performance of the alloys during a two-year atmospheric exposure and the corrosion rates calculated from electrochemical (polarization resistance) measurements.

  4. Chloride-free processing of aluminum scrap to recover by-product materials

    SciTech Connect

    Riley, W.D.; Jong, B.W.

    1995-12-31

    The US Bureau of Mines has developed technology to recover by-product materials from aluminum scrap using engineered scavenger compounds (ESC). ESCs are structural oxides with a channel or tunnel structure that allows them to hold ions of a specific sizes and charges. The scavenging reaction is easily reversible allowing the ESC to be recharged for continued use and the ion is recovered as an electrodeposit. Key features of this novel technology are: (a) ESC systems are designed to have a high degree of selectivity for a desired ionic species. (b) The recovered material requires little or no additional reprocessing prior to reuse. Two current uses for the ESC technology that are described in this paper are the removal and recycle of lithium (Li) from lithium aluminum (Li-Al) alloys; and, using ESCs as a replacement for the conventional demaging (magnesium removal) technology used by the secondary casting industry. Research indicates that the ESC technology proposed for both these applications has either distinct economic and/or environmental advantages over previously employed methods of recovering metal values from aluminum scrap.

  5. The containment of oil spills in porous media using xanthan/aluminum solutions, gelled by gaseous CO2 or by AlCl3 solutions.

    PubMed

    Gioia, Francesco; Ciriello, Pier Paolo

    2006-12-01

    The gelation in situ of polymers may be a method for temporarily containing organic solvents and other petroleum derived products, which may enter the subsurface. In order to create gels that are neither toxic to humans nor to the ecosystem, we have investigated on the use of the biopolymer xanthan gum with aluminum as a crosslinking agent. Firstly we have considered xanthan/sodium aluminate solutions, which upon preparation are strongly basic and do not gel. The gelation takes place in acid solutions so that Al(III) ions are released, and is instantaneous. Therefore, a special technique must be used for generating the gel structure in situ. The un-gelled solution must be injected and an acid must be added afterwards. We have investigated on the gelling reaction induced by gaseous carbon dioxide, which is an acid gas. The insufflation of CO(2) above the solution generates a layer of gel whose thickness progressively increases as CO(2) diffuses in the polymer solution. Secondly we have investigated on the use of aluminum chloride as the source of Al(III) ions. Also in this case, due to the full availability of Al(III) ions, the gelling reaction would be instantaneous. Therefore, the solution of AlCl(3) must be added on the top of the xanthan solution after its injection. For both gelling systems we have studied both theoretically and experimentally the rate of formation of the gel layer which progressively thickens after the insufflation of CO(2) or after the addition of the AlCl(3) solution. PMID:16935417

  6. Sodium chloride methanol solution spin-coating process for bulk-heterojunction polymer solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Tong-Fang; Hu, Yu-Feng; Deng, Zhen-Bo; Li, Xiong; Zhu, Li-Jie; Wang, Yue; Lv, Long-Feng; Wang, Tie-Ning; Lou, Zhi-Dong; Hou, Yan-Bing; Teng, Feng

    2016-08-01

    The sodium chloride methanol solution process is conducted on the conventional poly(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) polymer bulk heterojunction solar cells. The device exhibits a power conversion efficiency of up to 3.36%, 18% higher than that of the device without the solution process. The measurements of the active layer by x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and ultraviolet photoelectron spectroscopy (UPS) indicate a slight phase separation in the vertical direction and a sodium chloride distributed island-like interface between the active layer and the cathode. The capacitance–voltage (C–V) and impedance spectroscopy measurements prove that the sodium chloride methanol process can reduce the electron injection barrier and improve the interfacial contact of polymer solar cells. Therefore, this one-step solution process not only optimizes the phase separation in the active layers but also forms a cathode buffer layer, which can enhance the generation, transport, and collection of photogenerated charge carriers in the device simultaneously. This work indicates that the inexpensive and non-toxic sodium chloride methanol solution process is an efficient one-step method for the low cost manufacturing of polymer solar cells. Project supported by the Fundamental Research Funds for the Central Universities, China (Grant No. 2014JBZ009) and the National Natural Science Foundation of China (Grant Nos. 61274063, 61377028, 61475014, and 61475017).

  7. Solvation of lithium chloride in aqueous and mixed solutions of an aprotic solvent

    NASA Astrophysics Data System (ADS)

    Zabolotskii, V. I.; Demin, A. V.; Demina, O. A.

    2013-02-01

    The dynamic hydration and solvation numbers of lithium chloride are estimated on the basis of experimental data on the limiting electrodialysis concentration of an electrolyte from aqueous and aqueousorganic solutions containing aprotic solvent N,N-dimethylacetamide. It is established that the dependence of the hydration numbers of the salt on the volume fraction of the aprotic solvent is of an extreme character, and its solvation number on N,N-dimethylacetamide does not depend on the composition of the mixed solution.

  8. Storage of platelets in additive solutions: a new method for storage using sodium chloride solution.

    PubMed

    Gulliksson, H; Sallander, S; Pedajas, I; Christenson, M; Wiechel, B

    1992-06-01

    The in vitro effect of 6-day storage of platelets prepared from 6 pooled buffy coat (BC) units and stored in a platelet storage medium containing approximately 40 percent CPD-plasma and 60 percent platelet additive solution (PAS) was evaluated. PAS is composed of sodium and potassium chloride, citrate, phosphate, and mannitol. The total count of platelets per pooled unit included in the in vitro studies (n = 25) was 376 +/- 59 x 10(9) (mean +/- SD). The present study included three steps. 1. Evaluation of platelet storage in one (n = 7) and two (n = 6) 1000-mL polyolefin containers using PAS. During storage in one container, significantly lower values were found for pH, pO2, glucose, ATP, and the ratio of ATP to AMP+ADP+ATP. The values for mean platelet volume, pCO2, lactate, and extracellular adenylate kinase activity were significantly higher. These results indicate that storage in only one polyolefin container is not appropriate for maintaining satisfactory platelet quality. During storage in two polyolefin containers, a remarkably decreased lactate production (0.07 +/- 0.02 mmol/day/10(11) platelets) was noted. 2. PAS was substituted for saline during 6-day storage in two 1000-mL polyolefin containers (n = 12). The composition of the platelet preparations was the same in all other respects. Similar in vitro results were noted with PAS and saline, which indicated that PAS has no specific effect on the storage of platelets different from that of saline.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1626346

  9. Transmittance of distilled water and sodium-chloride-water solutions

    SciTech Connect

    Kanayama, K.; Baba, H.

    1988-05-01

    The spectral transmittance of pure water and salt water solutions of various concentrations, which are important for the thermal calculation of a solar pond, is measured experimentally for specimen thickness of 1 to 100 mm by means of an autorecording spectro-radiometer inside an air-conditioned room. On the basis of the measured spectral transmittance, the total transmittance of pure and salty waters to 3 m of water depth is calculated as a ratio of the total radiation energy over all wavelengths arriving at any depth from the water surface of the solar pond to the solar radiation incident upon the water surface with various air masses. According to Nielsens' four-partition method, the effective absorption coefficient is calculated for each wavelength band. Lastly, the transmission properties obtained for pure water, i.e., spectral and total transmittances, absorption wavelength band, and effective absorption coefficient, are compared with past results, and those for salty water with various concentrations are compiled as basic data for the use of solar energy by a solar pond.

  10. Aluminum-induced changes in properties and fouling propensity of DOM solutions revealed by UV-vis absorbance spectral parameters.

    PubMed

    Zhou, Minghao; Meng, Fangang

    2016-04-15

    The integration of pre-coagulation with ultrafiltration (UF) is expected to not only reduce membrane fouling but also improve natural organic matter (NOM) removal. However, it is difficult to determine the proper coagulant dosage for different water qualities. The objective of this study was to probe the potential of UV-vis spectroscopic analysis to reveal the coagulant-induced changes in the fouling potentials of dissolved organic matter (DOM) and to determine the optimal coagulant dosage. The Zeta potentials (ZPs) and average particle size of the four DOM solutions (Aldrich humic acid (AHA), AHA-sodium alginate (SA), AHA-bovine serum albumin (BSA) and AHA-dextran (DEX)) coagulated with aluminum chloride (AlCl3) were measured. Results showed that increasing the aluminum coagulant dosage induced the aggregation of DOM. Meanwhile, the addition of aluminum coagulant resulted in an increase in DSlope(325-375) (the slope of the log-transformed absorbance spectra from 325 to 375 nm) and a decrease in S(275-295) (the slope of the log-transformed absorption coefficient from 275 to 295 nm) and SR (the ratio of Slope(275-295) and Slope(350-400)). The variations of these spectral parameters (i.e., DSlope(325-375), S(275-295) and SR) correlated well with the aluminum-caused changes in ZPs and average particle size. This implies that spectral parameters have the potential to indicate DOM aggregation. In addition, good correlations of spectral parameters and membrane fouling behaviors (i.e., unified membrane fouling index (UMFI)) suggest that the changes in DSlope(325-375), S(275-295) and SR were indicative of the aluminum-caused alterations of fouling potentials of all DOM solutions. Interestingly, the optimal dosage of aluminum (40 μM for AHA, AHA-BSA, and AHA-DEX) was obtained based on the relation between spectral parameters and fouling behaviors. Overall, the spectroscopic analysis, particularly for the utilization of spectral parameters, provided a convenient approach

  11. Behavior of antimony(III) during copper electrowinning in chloride solutions

    SciTech Connect

    Lin, H.K.; Wu, X.

    1996-04-01

    Contamination of cathodic copper by Sb during electrowinning in chloride solutions is a surface phenomenon. A digitized scanning electron microscopy (SEM) micrograph indicates that the Sb is concentrated on the surface /of the cathode. Energy-dispersive X-ray (EDX) analysis reveals that the Sb-containing layer is a complex salt of Cu, Sb, Cl, and O. Electrochemical measurements show that the adsorption of Sb or Cu species decreases with the increase of acidity of the solution when the solution contains antimony chloride or cuprous chloride. The adsorption increases with the increase of the acidity when the solution contains both Sb and Cu. The discharge of cuprous ions in the adsorbed complex salt releases antimonious ions and then forms a new layer of the complex salt with cuprous ions from the solution. This newly formed complex salt is readsorbed on the surface of the cathode. Thus, Sb concentrates on the surface of the cathode instead of being evenly distributed throughout the copper product. This suggested mechanism also explains the fact that the presence of Sb in the electrolyte enhances the electrodeposition of Cu.

  12. Corrosion resistance of flaky aluminum pigment coated with cerium oxides/hydroxides in chloride and acidic electrolytes

    NASA Astrophysics Data System (ADS)

    Niroumandrad, S.; Rostami, M.; Ramezanzadeh, B.

    2015-12-01

    The objective of this study was to enhance the corrosion resistance of lamellar aluminum pigment through surface treatment by cerium oxides/hydroxides. The surface composition of the pigments was studied by energy-dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The corrosion resistance of the pigment was evaluated by conventional hydrogen evolution measurements in acidic solution and electrochemical impedance spectroscopy (EIS) in 3.5% NaCl solution. Results showed that the Ce-rich coating composed of Ce2O3 and CeO2 was precipitated on the pigment surface after immersion in the cerium solution. The corrosion resistance of pigment was significantly enhanced after modification with cerium layer.

  13. Respiratory symptoms among glass bottle makers exposed to stannic chloride solution and other potentially hazardous substances

    SciTech Connect

    Levy, B.S.; Davis, F.; Johnson, B.

    1985-04-01

    Concern about upper respiratory tract irritation and other symptoms among workers at a glass bottle manufacturing plant led to an epidemiologic and an industrial hygiene survey. Questionnaire responses from 35 hot end and 53 cold end workers indicated that the incidence of wheezing, chest pain, dyspnea on exertion, and cough was significantly elevated among hot end workers. Among both smokers and nonsmokers, hot end workers reported higher, but not significantly higher, rates of wheezing and chest pain. Among smokers, hot end workers reported significantly higher rates of dyspnea on exertion and cough than did cold end workers. Data suggest that reported exposure to stannic chloride solution likely caused these symptoms. The industrial hygiene survey, conducted when stannic chloride use had been reduced, cleaning had been done, and ventilation improved, focused on measuring air contaminants that might possibly cause symptoms. Levels of hydrogen chloride, which apparently was formed by the combination of stannic chloride and water in the presence of heat, were elevated. The finding of increased prevalence of respiratory symptoms among hot end workers was consistent with this exposure. Recommendations were made to reduce hazardous exposures at this plant. Individuals responsible for occupational health should be aware that relatively benign substances, such as stannic chloride and water, can combine spontaneously to form hazardous substances.

  14. The optical constants of several atmospheric aerosol species - Ammonium sulfate, aluminum oxide, and sodium chloride

    NASA Technical Reports Server (NTRS)

    Toon, O. B.; Pollack, J. B.; Khare, B. N.

    1976-01-01

    An investigation is conducted of problems which are related to a use of measured optical constants in the simulation of the optical constants of real atmospheric aerosols. The techniques of measuring optical constants are discussed, taking into account transmission measurements through homogeneous and inhomogeneous materials, the immersion of a material in a liquid of a known refractive index, the consideration of the minimum deviation angle of prism measurement, the interference of multiply reflected light, reflectivity measurements, and aspects of mathematical analysis. Graphs show the real and the imaginary part of the refractive index as a function of wavelength for aluminum oxide, NaCl, and ammonium sulfate. Tables are provided for the dispersion parameters and the optical constants.

  15. Crystallization of sodium chloride from a concentrated calcium chloride-potassium chloride-sodium chloride solution in a CMSMPR crystallizer: Observation of crystal size distribution and model validation

    NASA Astrophysics Data System (ADS)

    Choi, Byung Sang

    Compared to overwhelming technical data available in other advanced technologies, knowledge about particle technology, especially in particle synthesis from a solution, is still poor due to the lack of available equipment to study crystallization phenomena in a crystallizer. Recent technical advances in particle size measurement such as Coulter counter and laser light scattering have made in/ex situ study of some of particle synthesis, i.e., growth, attrition, and aggregation, possible with simple systems. Even with these advancements in measurement technology, to grasp fully the crystallization phenomena requires further theoretical and technical advances in understanding such particle synthesis mechanisms. Therefore, it is the motive of this work to establish the general processing parameters and to produce rigorous experimental data with reliable performance and characterization that rigorously account for the crystallization phenomena of nucleation, growth, aggregation, and breakage including their variations with time and space in a controlled continuous mixed-suspension mixed-product removal (CMSMPR) crystallizer. This dissertation reports the results and achievements in the following areas: (1) experimental programs to support the development and validation of the phenomenological models and generation of laboratory data for the purpose of testing, refining, and validating the crystallization process, (2) development of laboratory well-mixed crystallizer system and experimental protocols to generate crystal size distribution (CSD) data, (3) the effects of feed solution concentration, crystallization temperature, feed flow rate, and mixing speed, as well as different types of mixers resulting in the evolution of CSDs with time from a concentrated brine solution, (4) with statistically designed experiments the effects of processing variables on the resultant particle structure and CSD at steady state were quantified and related to each of those operating

  16. Solid reaction products and aluminate solutions that form during the operation of an air-aluminum chemical power supply

    NASA Astrophysics Data System (ADS)

    Okorokova, N. S.; Sevruk, S. D.; Suvorova, E. V.; Farmakovskaya, A. A.

    2015-12-01

    A solution to the set of problems concerning the solid reaction products and the aluminate solutions that form during the operation of an aluminum-closed power supply system for self-contained objects is proposed. The system is based on a resource-saving technology using an aluminum energy carrier in an air-aluminum chemical power supply and related energy installations. The boundaries of the metastable and labile state regions of aluminate solutions and the real degrees of supersaturation that can be attained when aluminum is dissolved in an electrolyte during the operation of an air-aluminum chemical power supply are determined.

  17. Aluminum chloride induces neuroinflammation, loss of neuronal dendritic spine and cognition impairment in developing rat.

    PubMed

    Cao, Zheng; Yang, Xu; Zhang, Haiyang; Wang, Haoran; Huang, Wanyue; Xu, Feibo; Zhuang, Cuicui; Wang, Xiaoguang; Li, Yanfei

    2016-05-01

    Aluminum (Al) is present in the daily life of humans, and the incidence of Al contamination increased in recent years. Long-term excessive Al intake induces neuroinflammation and cognition impairment. Neuroinflammation alter density of dendritic spine, which, in turn, influence cognition function. However, it is unknown whether increased neuroinflammation is associated with altered density of dendritic spine in Al-treated rats. In the present study, AlCl3 was orally administrated to rat at 50, 150 and 450 mg/kg for 90d. We examined the effects of AlCl3 on the cognition function, density of dendritic spine in hippocampus of CA1 and DG region and the mRNA levels of IL-1β, IL-6, TNF-α, MHC II, CX3CL1 and BNDF in developing rat. These results showed exposure to AlCl3 lead to increased mRNA levels of IL-1β, IL-6, TNF-α and MCH II, decreased mRNA levels of CX3CL1 and BDNF, decreased density of dendritic spine and impaired learning and memory in developing rat. Our results suggest AlCl3 can induce neuroinflammation that may result in loss of spine, and thereby leads to learning and memory deficits. PMID:26946116

  18. Aluminum(III) selective potentiometric sensor based on morin in poly(vinyl chloride) matrix.

    PubMed

    Gupta, Vinod K; Jain, Ajay K; Maheshwari, Gaurav

    2007-06-15

    Al(3+) selective sensor has been fabricated from poly(vinyl chloride) (PVC) matrix membranes containing neutral carrier morin as ionophore. Best performance was exhibited by the membrane having composition as morin:PVC:sodium tetraphenyl borate:tri-n-butylphosphate in the ratio 5:150:5:150 (w/w, mg). This membrane worked well over a wide activity range of 5.0x10(-7) to 1.0x10(-1)M of Al(3+) with a Nernstian slope of 19.7+/-0.1mV/decade of Al(3+) activity and a limit of detection 3.2x10(-7)M. The response time of the sensor is approximately 5s and membrane could be used over a period of 2 months with good reproducibility. The proposed sensor works well over a pH range (3.5-5.0) and demonstrates good discriminating power over a number of mono-, di- and trivalent cations. The sensor can also be used in partially non-aqueous media having up to 20% (v/v) methanol, ethanol or acetone content with no significant change in the value of slope or working activity range. The sensor has also been used in the potentiometric titration of Al(3+) with EDTA and for its determination in zinc plating mud and red mud. PMID:19071785

  19. Effects of three additives on the removal of perfluorooctane sulfonate (PFOS) by coagulation using ferric chloride or aluminum sulfate.

    PubMed

    Kishimoto, Naoyuki; Kobayashi, Masanori

    2016-01-01

    Perfluorooctanesulfonic acid and its salts (PFOS) are emerging contaminants with long half-lives in water and human bodies. Accordingly, PFOS removal from water streams is required for controlling the PFOS pollution. To provide a simple PFOS separation technology, effects of three additives, powdered activated carbon (PAC), gelatin, and cetyltrimethylammonium bromide (CTAB), on the PFOS removal by coagulation with ferric chloride or aluminum sulfate were investigated in this study. As a result, coagulation with PAC or CTAB addition was effective in the PFOS removal, though the conventional coagulation and coagulation with gelatin addition were ineffective. A PFOS removal efficiency of over 90% was observed for the CTAB dose of over 1.6 μM (0.58 mg/L) and for the PAC dose of over 40 mg/L, and that of over 95% was achieved by the CTAB dose of over 2.4 μM (0.87 mg/L), when the initial PFOS concentration was 1.84 μM. The positive effect of CTAB would be caused by micelle formation, which was enhanced by both the association of hydrophobic tails and the electrostatic attraction of hydrophilic heads of PFOS and CTAB. Thus, a linear cationic surfactant of CTAB was concluded to be an effective additive for the PFOS removal by coagulation. PMID:27332843

  20. Surface charge density on silica in alkali and alkaline earth chloride electrolyte solutions

    NASA Astrophysics Data System (ADS)

    Dove, Patricia M.; Craven, Colin M.

    2005-11-01

    The surface charge density of colloidal SiO 2 (Aerosil 380) was measured in alkali chloride (0.067 and 0.20 M LiCl, NaCl, and KCl) and alkaline earth chloride (0.067 M MgCl 2, CaCl 2, SrCl 2, BaCl 2) solutions. Measurements were conducted at 25°C by potentiometric titrations using the constant ionic medium method in a CO 2-free system. The experimental design measured surface charge for solutions with constant ionic strength as well as constant cation concentration. Alkali chloride solutions promote negative surface charge density in the order LiCl < NaCl < KCl to give the "regular" lyotropic behavior previously reported. In contrast, the alkaline earth chloride solutions exhibit a reversed lyotropic trend with increasing crystallographic radius where increasing negative charge is promoted in the order BaCl 2 < SrCl 2 < CaCl 2 < MgCl 2. The origin of the opposing affinity trends is probed by testing the hypothesis that this reversal is rooted in the differing solvent structuring characteristics of the IA and IIA cations at the silica-water interface. This idea arises from earlier postulations that solvent structuring effects increase entropy through solvent disordering and these gains must be much greater than the small, positive enthalpy associated with electrostatic interactions. By correlating measured charge density with a proxy for the solvent-structuring ability of cations, this study shows that silica surface charge density is maximized by those electrolytes that have the strongest effects on solvent structuring. We suggest that for a given solid material, solvation entropy has a role in determining the ionic specificity of electrostatic interactions and reiterate the idea that the concept of lyotropy is rooted in the solvent-structuring ability of cations at the interface.

  1. Internal pressures and molecular dimensions in aqueous solutions of some chlorides

    NASA Technical Reports Server (NTRS)

    Auslaender, D.; Lenart, I.; Rus, E.; Ciupe, A.

    1974-01-01

    On the basis of measurements of the velocity of ultrasounds in aqueous solutions of some alkaline-earth chlorides (MgCl2, CaCl2, BaCl2) the concentration and temperature dependences of the internal pressure were determined. Using these results, as well as surface tension measurements, the mean diameters of the molecular species as a function of concentration and temperature, were determined.

  2. Performance of cellulose acetate butyrate membranes in hyperfiltration of sodium chloride and urea feed solution

    NASA Technical Reports Server (NTRS)

    Wydeven, T.; Leban, M.

    1973-01-01

    Cellulose acetate butyrate (CAB) membranes are shown to give high salt and urea rejection with water flux of about 3 gallons/sq ft per day at 600 psig. Membranes prepared from a formulation containing glyoxal show a significant increase in flux and decrease in salt and urea rejection with drying time. Zero drying time gives maximum urea and salt rejection and is therefore most suitable for hyperfiltration of sodium chloride and urea feed solution.

  3. Primary stage of the reaction between ozone and chloride ions in aqueous solution: Can chloride ion oxidation by ozone proceed via electron transfer mechanism?

    NASA Astrophysics Data System (ADS)

    Levanov, A. V.; Antipenko, E. E.; Lunin, V. V.

    2012-04-01

    It is found that chloride-ion oxidation by ozone via electron transfer mechanism does not occur due to its extremely high endoergicity and negligibly low rate. It is concluded that all processes supposedly associated with this reaction, particularly ozone decomposition in sodium chloride solution initiated by Cl· atoms, do not take place either. It is shown that experimental data on the products and kinetic regularities of the interaction of O3 with Cl- contradict the assumption that the electron transfer reaction is its primary stage. In fact, chloride-ion oxidation by ozone proceeds via the mechanism of oxygen atom transfer. It is noted that in order to estimate the possibility of using an ozonated physiological saline in medicine, the formation of chloride-ion oxidation products and ozonation byproducts must be taken into account.

  4. Effect of aging on aluminum hydroxide complexes in dilute aqueous solutions

    USGS Publications Warehouse

    Smith, Ross Wilbert; Hem, John David

    1972-01-01

    Aqueous aluminum solutions containing 4?10 -5 mole/liter aluminum and a constant total ionic strength of 10 -2, but with varying ratios of hydroxide to aluminum (OH:Al), were prepared. Progress of these solutions toward equilibrium conditions over aging periods of as much as 2 years was studied by determining the composition and pH of the solutions at various time intervals. The solutions, after mixing, were supersaturated with respect to both crystalline and amorphous forms of aluminum oxides and aluminum hydroxides. The compositions of the solutions were determined by use of a timed colorimetric analytical procedure which allowed the estimation of three separate forms of aluminum that have been designated Al a, Al b, and Al c. Form Al a appeared to be composed of monomeric species such as Al(H20)6+3, Al(OH)(H20)5+2, Al(OH)2(H20)4 +I and Al(OH)4-. Form Al b was polynuclear material containing perhaps 20-400 aluminum atoms per structure. It appeared to be a metastable material. Form Al c was composed of relatively large, microcrystalline, clearly solid AI(OH)3 particles. For each OH :Al ratio, the concentration of Al a remained constant with aging time, Al b decreased, and Al c increased. It appeared that Al b particles were increasing in size and ultimately were converted to Al c particles. After a few weeks' aging, Al c particles had the structure of gibbsite. In all solutions, equilibrium was only very slowly achieved, and the time required depended on the OH:Al ratio and how rapidly the solution was initially prepared (mixing time). Lower ratios caused a slower approach to equilibrium; sometimes equilibrium was not achieved even after several years' aging. The more slowly base was initially added (to obtain the proper OH:Al ratio), the more slowly was equilibrium approached. Ultimate equilibrium values of dissolved aluminum concentration and pH were consistent with known thermodynamic data on monomeric aluminum species. From data determined during the aging

  5. Spectroscopic analysis of aluminum chloride phthalocyanine in binary water/ethanol systems for the design of a new drug delivery system for photodynamic therapy cancer treatment

    NASA Astrophysics Data System (ADS)

    Jayme, Cristiano Ceron; Calori, Italo Rodrigo; Tedesco, Antonio Claudio

    2016-01-01

    This study evaluated the behavior of aluminum chloride phthalocyanine in a binary water/ethanol mixture using electronic absorption spectroscopy and static and time-resolved fluorescence spectroscopy. The electronic absorption spectra, resonance light scattering and fluorescence quenching of aluminum chloride phthalocyanine in water/ethanol mixtures were studied at several concentrations. The electronic absorption spectra and fluorescence quenching changed significantly at approximately 50% water (v/v). Below 50% water, the dimerization constant values were negative (- 2609.2 M- 1 and - 506.5 M- 1 at 30% and 40% of water, respectively), indicating that the formation of aggregates under these conditions is not favored. However, at 50% water, the dimerization constant value was estimated to be 559.7 M- 1, which indicates the presence of dimers. Above 60% water, the aggregation process was responsible for the balance between large complexes (such as trimers, tetramers or oligomers) formed in the medium under these conditions. The appearance of new absorption bands at 387 nm and 802 nm and their bathochromic shift relative to the monomer bands suggested that some J-type aggregates form. These results are relevant to understanding the behavior and use of aluminum chloride phthalocyanine in the design of new drug delivery systems for clinical application in photodynamic therapy as a new approach to treat skin cancer.

  6. Concentrations of aluminum in gut tissue of crayfish (Procambarus clarkii), purged in sodium chloride

    SciTech Connect

    Madigosky, S.R.; Alvarez-Hernandez, X.; Glass, J.

    1992-10-01

    Recent concern over the release of Al in the environment has prompted researchers and health officials to assess its effects on biological systems. Aluminum, despite being the most abundant metal in earth`s lithosphere, is normally complexed in soil and is therefore unavailable for biological assimilation. The recent advent of acid rain, however, has prompted Al release due to mobilization from surrounding sediments into the environment. This is of particular concern in aquatic environments because organisms in aquatic food chains can access and concentrate sublethal levels of Al in their tissues relatively quickly. The ingestion of affected organisms by humans may therefore pose a potential health risk. One such organism, is known to concentrate metals in a variety of tissues. In northern Louisiana, many people trap or fish for crayfish in lowland areas which lie adjacent to highways and secondary roadways. Water, soil, and crayfish from these areas are known to contain high levels of Al. Some tissues known to concentrate Al (muscle, hepatopancreas and intestine tissue and contents) are those which humans commonly consume. The ingestion of these tissues may therefore expose humans to elevated Al levels. Many people who eat crayfish often purge them in dilute concentrations (1-2%) of NaCl to rid them of contaminants and make them more palatable. We are aware of no literature which corroborates the claim that purging removes contaminating metals. The objectives of this study were to (1) document the amount of Al found in water, soil, and gut tissue of crayfish (P. clarkii) collected from a roadside wetland site; (2) determine the affect of NaCl purging on the release of Al in P. clarkii and (3) assess the differences in Al levels found between stomach tissue, stomach tissue contents, intestine tissue, and intestine contents in P. clarkii. 12 refs., 3 figs., 1 tab.

  7. Dendrite-Free Aluminum Electrodeposition from AlCl3-1-Ethyl-3-Methyl-Imidazolium Chloride Ionic Liquid Electrolytes

    NASA Astrophysics Data System (ADS)

    Pradhan, Debabrata; Reddy, Ramana G.

    2012-06-01

    A novel, dendrite-free electrorefining of aluminum scrap alloys (A360) was investigated by using a low-temperature AlCl3-1-ethyl-3-methyl-imidazolium chloride (EMIC) ionic liquid electrolyte on copper/aluminum cathodes. The bulk electrodeposition of aluminum was carried out at a fixed voltage of 1.5 V, temperatures 323 K to 383 K (50 °C to 110 °C), stirring rate (0 to 120 rpm), concentration (molar ratio AlCl3:EMIC = 1.25 to 2.0), and electrode surface modification (modified/unmodified). The study investigated the effect of electrode surface modification, cathode materials, temperature, stirring rate, electrolyte concentration, and deposition time on the deposit morphology of aluminum, cathode current density, and their role in production of dendrite-free aluminum deposit, which is essential for decreasing the production cost. The deposits were characterized using scanning electron microscope (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD). It was shown that electrode surface modification, cathode overpotential, and stirring rate play an important role in dendrite-free deposit. Modified electrodes and stirring (60 rpm) eliminate dendritic deposition by reducing cathode overpotential below critical overpotential ( η_{{crt}} ≈ - 0.53V ) for dendrite formation. Pure aluminum (>99 pct) was deposited for all experiments with a current efficiency of 84 to 99 pct and energy consumption of 4.51 to 5.32 kWh/kg Al.

  8. A portable air-aluminum power source with an alkaline electrolytic solution

    NASA Astrophysics Data System (ADS)

    Alekseenko, S. V.; Galkin, P. S.; Kashinskii, O. N.; Markovich, D. M.; Novopashin, S. A.; Randin, V. V.; Kharlamov, S. M.

    2014-04-01

    The results from development of a portable air-aluminum chemical power source (AA CPS) with an alkaline electrolytic solution without any additional service circuits are presented. The feasibility of making air cathodes on the basis of a metal-carbon composite produced by the plasma method has been shown. Special features of the operational conditions of a portable AA CPS have been investigated. It has been found that the aluminum cathode passivation when aluminum hydroxide precipitates from a solution significantly restricts the specific capacity of such power sources. It was shown that it is possible to overcome the anode passivation and to considerably increase the specific capacity of an AA CPS with an alkaline electrolytic solution by means of modifying an anode alloy.

  9. The initial release of zinc and aluminum from non-treated Galvalume and the formation of corrosion products in chloride containing media

    NASA Astrophysics Data System (ADS)

    Zhang, Xian; Vu, Thanh-Nam; Volovitch, P.; Leygraf, C.; Ogle, K.; Wallinder, I. Odnevall

    2012-03-01

    This study explores the initial release of zinc and aluminum from non-treated Galvalume and the parallel formation of corrosion products when exposed to synthetic seawater and rainwater of different chloride content. Comparisons were made with long-term field exposures at non-sheltered marine conditions. Observed release rates from short-term conditions agree qualitatively with the long-term findings with a selective release of zinc over aluminum. The release and corrosion processes were intertwined through the formation of corrosion products with properties that influence the long-term release process. Prior to exposure, Al2O3 dominated the entire surface, and was subject to local destruction upon interaction with chloride ions. As a consequence Al2O3 was gradually replaced and covered by zinc-rich corrosion products primarily in interdendritic areas during the first year of marine exposure. This was followed by the gradual formation and integration of aluminum-rich corrosion products, reflected by an increased zinc release rate during the first year, followed by a gradually decreased rate during subsequent years. The importance of Al2O3 was also evident in deaerated synthetic rainwater or seawater, where the formation of Al2O3 was presumably hindered. In synthetic rain water this resulted in a higher ratio between released aluminum and zinc compared with non-deaerated conditions.

  10. Pitting of steam-generator tubing alloys in solutions containing thiosulfate and sulfate or chloride.

    PubMed

    Zhang, William; Carcea, Anatolie G; Newman, Roger C

    2015-01-01

    The pitting of nuclear steam generator tubing alloys 600, 690 and 800 was studied at 60 °C using dilute thiosulfate solutions containing excess sulfate or (for Alloy 600) chloride. A potentiostatic scratch method was used. In sulfate solutions, all alloys pitted at low potentials, reflecting their lack of protective Mo. The alloys demonstrated the most severe pitting at a sulfate : thiosulfate concentration ratio of ∼40. Alloy 600 pitted worst at a chloride : thiosulfate ratio of ∼2000. The results are interpreted through the mutual electromigration of differently charged anions into a pit nucleus, and differences in the major alloy component. PMID:25898311

  11. Photochemical oxidation of chloride ion by ozone in acid aqueous solution.

    PubMed

    Levanov, Alexander V; Isaykina, Oksana Ya; Amirova, Nazrin K; Antipenko, Ewald E; Lunin, Valerii V

    2015-11-01

    The experimental investigation of chloride ion oxidation under the action of ozone and ultraviolet radiation with wavelength 254 nm in the bulk of acid aqueous solution at pH 0-2 has been performed. Processes of chloride oxidation in these conditions are the same as the chemical reactions in the system O3 - OH - Cl(-)(aq). Despite its importance in the environment and for ozone-based water treatment, this reaction system has not been previously investigated in the bulk solution. The end products are chlorate ion ClO3(-) and molecular chlorine Cl2. The ions of trivalent iron have been shown to be catalysts of Cl(-) oxidation. The dependencies of the products formation rates on the concentrations of O3 and H(+) have been studied. The chemical mechanism of Cl(-) oxidation and Cl2 emission and ClO3(-) formation has been proposed. According to the mechanism, the dominant primary process of chloride oxidation represents the complex interaction with hydroxyl radical OH with the formation of Cl2(-) anion-radical intermediate. OH radical is generated on ozone photolysis in aqueous solution. The key subsequent processes are the reactions Cl2(-) + O3 → ClO + O2 + Cl(-) and ClO + H2O2 → HOCl + HO2. Until the present time, they have not been taken into consideration on mechanistic description and modelling of Cl(-) oxidation. The final products are formed via the reactions 2ClO → Cl2O2, Cl2O2 + H2O → 2H(+) + Cl(-) + ClO3(-) and HOCl + H(+) + Cl(-) ⇄ H2O + Cl2. Some portion of chloride is oxidized directly by O3 molecule with the formation of molecular chlorine in the end. PMID:26077317

  12. Aluminum hydroxide nucleation kinetics and mechanism during the electrodialysis decomposition of aluminate solutions

    NASA Astrophysics Data System (ADS)

    Lainer, Yu. A.; Gorichev, I. G.; Todorov, S. A.

    2008-08-01

    The kinetic laws of the electrodialysis decomposition of strong aluminate solutions are considered. Mathematical simulation is performed using the equations of the heterogeneous kinetics of aluminum hydroxide precipitation for the electrodialysis of aluminate solutions, and this simulation shows that the nature of the limiting stage is related to the instantaneous nucleation during the three-dimensional coalescence of particles. The electrodialysis precipitate is analyzed, and the possible commercial application of the decomposition of strong aluminate solutions by electrodialysis is considered.

  13. Erythrocyte lysis in isotonic solution of ammonium chloride: theoretical modeling and experimental verification.

    PubMed

    Chernyshev, Andrey V; Tarasov, Peter A; Semianov, Konstantin A; Nekrasov, Vyacheslav M; Hoekstra, Alfons G; Maltsev, Valeri P

    2008-03-01

    A mathematical model of erythrocyte lysis in isotonic solution of ammonium chloride is presented in frames of a statistical approach. The model is used to evaluate several parameters of mature erythrocytes (volume, surface area, hemoglobin concentration, number of anionic exchangers on membrane, elasticity and critical tension of membrane) through their sphering and lysis measured by a scanning flow cytometer (SFC). SFC allows measuring the light-scattering pattern (indicatrix) of an individual cell over the angular range from 10 degrees to 60 degrees . Comparison of the experimentally measured and theoretically calculated light scattering patterns allows discrimination of spherical from non-spherical erythrocytes and evaluation of volume and hemoglobin concentration for individual spherical cells. Three different processes were applied for erythrocytes sphering: (1) colloid osmotic lysis in isotonic solution of ammonium chloride, (2) isovolumetric sphering in the presence of sodium dodecyl sulphate and albumin in neutrally buffered isotonic saline, and (3) osmotic fragility test in hypotonic media. For the hemolysis in ammonium chloride, the evolution of distributions of sphered erythrocytes on volume and hemoglobin content was monitored in real-time experiments. The analysis of experimental data was performed in the context of a statistical approach, taking into account that parameters of erythrocytes vary from cell to cell. PMID:18083194

  14. Removal of sodium and chloride ions from aqueous solutions using fique fibers (Furcraea spp.).

    PubMed

    Agudelo, Nikolay; Hinestroza, Juan P; Husserl, Johana

    2016-01-01

    Fique fibers obtained from the leaves of Furcraea spp., a highly abundant plant in the mountains of South America, may offer an alternative as biosorbents in desalination processes as they exhibit high removal capacities (13.26 meq/g for chloride ions and 15.52 meq/g for sodium ions) up to four times higher than exchange capacities commonly observed in synthetic resins. The ion removal capacity of the fibers was also found to be a function of the pH of the solution with the maximum removal of ions obtained at pH 8. Unlike most commercial ion exchange resins, our results suggest that fique fibers allow simultaneous removal of chloride and sodium ions. PMID:26942543

  15. Occurrence of aluminum in chloride cells of Perla marginata (Plecoptera) after exposure to low pH and elevated aluminum concentration

    SciTech Connect

    Guerold, F.; Giamberini, L.; Pihan, J.C.; Tourmann, J.L.; Kaufmann, R.

    1995-04-01

    As a consequence of acid depositions on poorly buffered catchments underlain by hard rocks, aluminum is mobilized and transported from terrestrial systems to the aquatic environment. Loss of fishes has been related to low pH and elevated aluminum concentrations in surface waters which present a low ionic content especially during acid stress such as snowmelt and heavy rainfalls. Among the causes of fish population decline in acid waters, aluminum is considered a toxic cofactor. Different studies have clearly shown that aluminum is accumulated in different organs such as kidneys, liver and gills. Research on fish has demonstrated that aluminum may be toxic, but the toxicity is markedly influenced by the pH, organic compounds and calcium content of the water. Field surveys have shown clearly that macroinvertebrates are also affected by surface-water acidification. However, little is know about the possible effects of aluminum on aquatic invertebrates and, particularly, on aquatic insects exposed to acidic conditions. Hall et al. have shown that the whole-body concentration of aluminum decreases in blackflies and mayflies transplated from neutral water to acid water. Similar results have been reported for Daphnia and chironomid. On the contrary, Ormerod et al. demonstrated the absence of relationship between water pH and insect aluminum concentrations. When aluminum occurs in aquatic insects, it has been shown that it is primarily adsorbed on the external surface and/or accumulates in gut contents. To our knowledge, the subcellular location as well as the toxicity of aluminum to acid-sensitive aquatic insects remains unclear and existing hypotheses are often based on research on fish. In this content the purpose of this study was to investigate the presence of aluminum at a subcellular level in the acid-sensitive species of stonefly, Perla marginata, after exposure to low pH and elevated aluminum concentrations. 18 refs., 1 fig., 1 tab.

  16. Biocompatibility of a xenogenic elastin-based biomaterial in a murine implantation model: the role of aluminum chloride pretreatment.

    PubMed

    Hinds, Monica T; Courtman, David W; Goodell, Teresa; Kwong, Mason; Brant-Zawadzki, Halina; Burke, Allen; Fox, Bernard A; Gregory, Kenton W

    2004-04-01

    We have investigated the long-term effect of aluminum chloride (AlCl(3)) treatment on the calcification and inflammatory reaction of a porcine elastin-derived biomaterial (PEB) in a novel subdermal adult mouse model. Untreated PEB disks and PEB treated with AlCl(3) were implanted subdermally in BALB/c mice for 30, 60, and 180 days. The calcification of the elastin disks was examined with histological analysis and atomic absorption analysis of calcium content. The inflammatory reaction was evaluated both with histological analysis of explants and by an enzyme-linked immunosorbent assay of the serum in each mouse to determine the production of antielastin antibodies. Robust calcification was evident in all untreated PEBs with calcium levels of 107.1 +/- 11.8, 151.4 +/- 14.4, and 227.2 +/- 23.8 microg/mg for 30, 60, and 180 days, respectively. AlCl(3) treatment only temporarily prevented the calcification of the elastin disks for 30 days. By 60 and 180 days, the AlCl(3)-treated materials had significant calcification with 88.7 +/- 17.4 and 105.3 +/- 27.0 microg/mg calcium, respectively. The inflammatory reaction was moderate for both types of implants. The AlCl(3)-treated implants displayed significantly more macrophage and lymphocyte infiltration at 180 days after implantation, and a trend to higher humoral responses at 30 and 60 days when compared with untreated PEBs. We conclude that PEBs extensively calcify in the adult mice model. AlCl(3) treatment of elastin enhances the long-term immunological response to xenogenic elastin implants and merely delays the onset of calcification. PMID:14999751

  17. Freezing of snow layers saturated with a calcium chloride aqueous solution

    NASA Astrophysics Data System (ADS)

    Sugawara, M.; Tago, M.; Nozawa, R.; Beer, H.

    2002-09-01

    This paper provides a basic information to control snow layers on roads or runways in order to maintain road safety. The snow saturated with a calcium chloride aqueous solution is initially in the thermodynamic equilibrium at the desired concentration and temperature. Since the snow layer bottom is quickly cooled by maintaining a fixed cooling wall temperature, the aqueous solution in the snow layer will freeze gradually upwards without natural convection in the layer due to the stable density distribution. It is seen that the temperature/concentration and the freezing volume fraction are affected by the cooling wall temperature and the initial concentration in the layer. A simple idealized numerical model predicts well the freezing behavior of the snow layer saturated with the aqueous solution.

  18. Low-frequency dynamics of aqueous alkali chloride solutions as probed by terahertz spectroscopy

    NASA Astrophysics Data System (ADS)

    Kann, Z. R.; Skinner, J. L.

    2016-06-01

    Terahertz (far infrared) spectroscopy provides a useful tool for probing both ionic motions in solution and the effect of ionic solutes on the dynamics of the solvent. In this study, we calculate terahertz spectra of aqueous alkali chloride solutions using classical but novel (the water model includes three-body interactions, the ion parameterization is non-standard, and the dipole surface is polarizable) molecular dynamics simulations. The calculated spectra compare reasonably well to experimental spectra. Decomposition of the calculated spectra is used to gain a deeper understanding of the physical phenomena underlying the spectra and the connection to, for instance, the vibrational density of states for the ions. The decomposed results are also used to explain many of the cation-dependent trends observed in the experimental spectra.

  19. Comparative estimate of the efficiency of the sorption extraction of iodine from chloride solutions

    NASA Astrophysics Data System (ADS)

    Nguen, Bao Din Kuok; Chernov'yants, M. S.; Burykin, I. V.; Anokhin, A. S.

    2012-12-01

    The possibility of applying activated carbon and polymeric sorbents poly(4-vinylpyridine), polytrimethylsilylpropyne (PTMSP), bromo-substituted PNMSP (Br-PNMSP), poly(N-methyl-4-vinylpyridinium iodide) for the sorption recovery of iodine from a 0.5 M solution of sodium chloride is studied. The dependence of iodine sorption on the pH of solution, the amount of adsorbent, and the duration of contact between the solution and adsorbent is studied. The highest sorption capacity ( G = 616.78 mg/g) is attained by using poly(N-methyl-4-vinylpyridinium iodide) anionite with the addition of iodine to form complex triiodide ions. The dynamics of iodine adsorption on poly(4-vinylpyridine) is described by a kinetic model of pseudosecond order. The composition and structure of the iodine compounds sorbed by polymers and activated carbon are studied by Raman spectroscopy (RS).

  20. Fluxional behavior of a cadmium zwitterion complex: proton transport and tautomerism in methylene chloride solution.

    PubMed

    Anderson, Oren P; la Cour, Agnete; Berg, Andrew; Garrett, Andrew D; Wicholas, Mark

    2003-07-28

    The synthesis and structure of the tautomeric Cd(II) isoindoline zwitterion coordination compound [Cd(4'-MeLH)(NO(3))(2)].CH(3)OH (4'-MeLH = 1,3-bis[2-(4-methylpyridyl)imino]isoindoline) are reported. In methylene chloride solution, tautomer interconversion occurs as the N-H proton moves between the identical imine nitrogen atoms. We report the kinetics of proton transfer as followed by variable temperature (1)H NMR spectroscopy and demonstrate that methanol of solvation and adventitious water facilitate rapid proton transfer. PMID:12870937

  1. Kinetic and spectrophotometric investigation of the diels-alder reaction between maleic anhydride derivatives and substituted anthracenes in the presence of gallium and aluminum chlorides

    SciTech Connect

    Kiselev, V.D.; Konovalov, A.I.; Shakirov, I.M.

    1986-10-01

    A comparison was made of the kinetic data for the normal Diels-Alder reaction of para-substituted N-arylmaleimides and substituted maleic anhydrides with meso-substituted anthracenes and of the reaction catalyzed by gallium and aluminum chlorides. The largely constant effects of gallium chloride (10/sup 4/) and aluminum chloride (10/sup 5/) in the acceleration of the reactions between the various pairs were demonstrated. The energies of charge transfer in the complexes between hexamethylbenzene and the dienophiles in the presence and absence of Lewis acids were determined by spectrophotometry. A significant decrease (to 1.2 eV) of the charge-transfer energy was found in the ..pi.., ..pi..-complexes and was attributed to the stabilization of the LUMO of the dienophile. From analysis of the obtained data it was concluded that the observed catalytic effect in the presence of Lewis acids can be explained by the approach of the frontier orbital levels and by a favorable change in the coefficients at the atomic orbitals responsible for the reaction.

  2. Adsorption and chemical reaction of gaseous mixtures of hydrogen chloride and water on aluminum oxide and application to solid-propellant rocket exhaust clouds

    NASA Technical Reports Server (NTRS)

    Cofer, W. R., III; Pellett, G. L.

    1978-01-01

    Hydrogen chloride (HCl) and aluminum oxide (Al2O3) are major exhaust products of solid rocket motors (SRM). Samples of calcination-produced alumina were exposed to continuously flowing mixtures of gaseous HCl/H2O in nitrogen. Transient sorption rates, as well as maximum sorptive capacities, were found to be largely controlled by specific surface area for samples of alpha, theta, and gamma alumina. Sorption rates for small samples were characterized linearly with an empirical relationship that accounted for specific area and logarithmic time. Chemisorption occurred on all aluminas studied and appeared to form from the sorption of about a 2/5 HCl-to-H2O mole ratio. The chemisorbed phase was predominantly water soluble, yielding chloride/aluminum III ion mole ratios of about 3.3/1 suggestive of dissolved surface chlorides and/or oxychlorides. Isopiestic experiments in hydrochloric acid indicated that dissolution of alumina led to an increase in water-vapor pressure. Dissolution in aqueous SRM acid aerosol droplets, therefore, might be expected to promote evaporation.

  3. Kinetics of leaching of the aluminum hydroxide in bauxites by alkaline solutions at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Burtsev, A. V.; Lainer, Yu. A.; Gorichev, I. G.; Kipriyanov, N. A.; Izotov, A. D.

    2011-11-01

    The kinetics of leaching of the aluminum hydroxide from the gibbsite bauxites of Guinea (Kindia deposit) is studied under atmospheric conditions. The activation energy of the process is found to be 34.75 kJ/mol, which indicates that the process proceeds in a kinetic mode. The leaching of the aluminum hydroxide from bauxite in an alkaline solution is simulated using acid-base equilibria (ion exchange) and the electrochemical theory of the structure of a double electrical layer (Gram-Parsons theory).

  4. Equilibrium dialysis and ultrafiltration investigations of perchlorate removal from aqueous solution using poly(diallyldimethylammonium) chloride.

    PubMed

    Roach, Jim D; Tush, Daniel

    2008-02-01

    Use of perchlorate salts in military activities and the aerospace industry is widespread. These salts are highly water-soluble and are, to a large extent, kinetically inert as aqueous species. As a groundwater contaminant, perchlorate is now being detected in an increasing number of locations and is believed to interfere with the uptake of iodide by the thyroid, which can result in decreased hormone production. The United States Environmental Protection Agency (US EPA) has established a reference dose for perchlorate of 0.0007 mg/kg/day, which translates to a drinking water equivalent level of 24.5 ppb. This study investigated the application of polyelectrolyte-enhanced ultrafiltration (PEUF) for the selective removal of perchlorate from aqueous solution through equilibrium dialysis and ultrafiltration experiments. Using poly(diallyldimethylammonium) chloride, the effectiveness and efficiency of PEUF in the removal of perchlorate from other aqueous solution components was investigated by testing parameters such as polyelectrolyte concentration, pH, and ionic strength. Removal of perchlorate from synthetic groundwater initially containing 10.3 ppm perchlorate and also containing chloride, sulfate, and carbonate was also examined. Perchlorate separations of greater than 95% were achieved, even in the presence of 10-fold excesses of competing ions. PMID:17915279

  5. Stability of buprenorphine, haloperidol and glycopyrrolate mixture in a 0.9% sodium chloride solution.

    PubMed

    Jäppinen, A; Kokki, H; Naaranlahti, T J; Rasi, A S

    1999-12-01

    Combinations of opioids and adjuvant drug solutions are often used in clinical practice while little information is available on their microbiological or chemical stability. Currently there are no commercially available, prepacked, ready-to-use epidural or subcutaneous mixtures. Thus, epidural and subcutaneous analgesic mixtures must be prepared in the pharmacy on an as-needed basis. Such mixtures are typically used for the treatment of severe pain in cancer patients. The aim of this study was to investigate the microbiological and chemical stability of a buprenorphine, haloperidol and glycopyrrolate mixture in a 0.9% sodium chloride solution. A high performance liquid chromatographic (HPLC) method and pH-meter were used to conduct the analyses. Antimicrobial activity of each component was studied by an agar dilution method. According to the results from the chemical and microbiological stability studies, this mixture can be stored in polypropylene (PP) syringes and polyvinyl chloride (PVC) medication cassettes for at least 30 days at either 21 degrees C or 4 degrees C, and for 16 days in PP syringes at 36 degrees C, and for 9 days in PVC medication cassettes at 36 degrees C. PMID:10658237

  6. Mechanism of the alkylation of benzene with propylene in the presence of an aluminosilicate catalyst modified by reaction of aluminum chloride with aromatic hydrocarbons. Catalyst promotion

    SciTech Connect

    Kolesnikov, I.M.; Zaitseva, T.V.

    1985-09-01

    The authors investigated the gas-liquid phase alkylation reaction of benzene with propylene in the presence of aluminosilicate catalysts which have been activated by treatment with varying amounts of the complex derived from aluminum chloride and polyalkylbenzene, and also studied the viability of various compounds as complex promoters. It was established that catalyst activity is enhanced by modification with the complex. The optimum concentration of complex (in the modified catalyst) is 15. wt. %. It was also established that isobutyl chloride added to the reaction mixture in the presence of the modified catalyst acts as a promoter and increases the activity of the catalyst twofold, to an acceptable level. The value of the energy of activation of the alkylation reaction was determined by kinetic analysis of the experimental data to be 38,300 J/mole.

  7. Effect of adamantane-containing additives on the isomerization of n-heptane in the ionic liquid trimethylammonium hydrochloride-aluminum chloride

    NASA Astrophysics Data System (ADS)

    Vasina, T. V.; Kustov, L. M.; Novakov, I. A.; Orlinson, B. S.

    2013-01-01

    We study the effect of adamantane-containing additives on the process of isomerization of n-heptane in the ionic liquid trimethylammonium hydrochloride-aluminum chloride (1 : 2 mol). It is shown that introducing 1-cyanomethyl-3-cyanoadamantane (5.0 wt %) into the reaction mixture slows conversion and lowers the yield of iso-products by a factor of more than 1.5, while adding adamantylpolyimide (0.5-5.0 wt %) substantially accelerates the isomerization of n-heptane and increases the yield of iso-products. In addition, this reaction proceeds under mild conditions at 40°C in the absence of hydrogen and precious metals.

  8. Interdiffusion in Ternary Magnesium Solid Solutions of Aluminum and Zinc

    DOE PAGESBeta

    Kammerer, Catherine; Kulkarni, Nagraj S; Warmack, Robert J Bruce; Sohn, Yong Ho

    2016-01-11

    Al and Zn are two of the most common alloying elements in commercial Mg alloys, which can improve the physical properties through solid solution strengthening and precipitation hardening. Diffusion plays a key role in the kinetics of these and other microstructural design relevant to Mg-alloy development. However, there is a lack of multicomponent diffusion data available for Mg alloys. Through solid-to-solid diffusion couples, diffusional interactions of Al and Zn in ternary Mg solid-solution at 400° and 450 °C were examined by an extension of the Boltzmann-Matano analysis based on Onsager s formalism. Concentration profiles of Mg-Al-Zn ternary alloys were determinedmore » by electron probe microanalysis, and analyzed to determine the ternary interdiffusion coefficients as a function of composition. Zn was determined to interdiffuse the fastest, followed by Mg and Al. Appreciable diffusional interactions among Mg, Al, and Zn were observed by variations in sign and magnitude of cross interdiffusion coefficients. In particular, Zn was found to significantly influence the interdiffusion of Mg and Al significantly: the and ternary cross interdiffusion coefficients were both negative, and large in magnitude, in comparison to and , respectively. Al and Mg were observed influence the interdiffusion of Mg and Al, respectively, with positive and interdiffusion coefficients, but their influence on the Zn interdiffusion was negligible.« less

  9. Leaching of lead from zinc leach residue in acidic calcium chloride aqueous solution

    NASA Astrophysics Data System (ADS)

    Wang, Le; Mu, Wen-ning; Shen, Hong-tao; Liu, Shao-ming; Zhai, Yu-chun

    2015-05-01

    A process with potentially reduced environmental impacts and occupational hazards of lead-bearing zinc plant residue was studied to achieve a higher recovery of lead via a cost-effective and environmentally friendly process. This paper describes an optimization study on the leaching of lead from zinc leach residue using acidic calcium chloride aqueous solution. Six main process conditions, i.e., the solution pH value, stirring rate, concentration of CaCl2 aqueous solution, liquid-to-solid (L/S) ratio, leaching temperature, and leaching time, were investigated. The microstructure and components of the residue and tailing were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). On the basis of experimental results, the optimum reaction conditions were determined to be a solution pH value of 1, a stirring rate of 500 r·min-1, a CaCl2 aqueous solution concentration of 400 g·L-1, a liquid-to-solid mass ratio of 7:1, a leaching temperature of 80°C, and a leaching time of 45 min. The leaching rate of lead under these conditions reached 93.79%, with an iron dissolution rate of 19.28%. Silica did not take part in the chemical reaction during the leaching process and was accumulated in the residue.

  10. Photodynamic therapy of murine non-melanoma skin carcinomas with diode laser after topical application of aluminum phthalocyanine chloride

    NASA Astrophysics Data System (ADS)

    Kyriazi, Maria; Alexandratou, Eleni; Yova, Dido; Rallis, Michail; Trebst, Tilmann

    2007-07-01

    The aim of this work is to study pharmacokinetics and photodynamic efficiency of aluminium phthalocyanine chloride (AlClPc) in dimethylsulfoxide/Tween 80/water solution, after topical application on hairless mice bearing non-melanoma skin carcinomas. The concentration of photosensitizer in normal skin and tumor biopsies 1-6 hours after application was assessed by fluorescence spectroscopy of chemical extractions. The concentration of photosensitizer was 40 times higher in tumor than in normal skin even 1 h after application. For photodynamic therapy (PDT) AlClPc was excited by a diode laser emitting at 670 nm, 1 h after application. Seven different combinations of therapeutic parameters were chosen. The efficiency was assessed as the percentage of complete tumor remission, the tumor growth retardation and the cosmetic outcomes. The highest complete remission 60% was achieved with the combination of 75 mW/cm2 with 150 J/cm2. No recurrence rate was observed in any treatment parameters group and the cosmetic outcome in all completely treated tumors was excellent. The results show that the effectiveness of PDT is highly dependent on fluence rate. In addition, they are promising for further investigation of this PDT scheme in preclinical studies mainly in non-melanoma skin carcinomas up to 7mm.

  11. Densitometry and ultrasound velocimetry of hyaluronan solutions in water and in sodium chloride solution.

    PubMed

    Kargerová, A; Pekař, M

    2014-06-15

    The densities of hyaluronan solutions in water and 0.15M NaCl were measured in the temperature range from 25 to 50°C for the hyaluronan molecular weights from 10 to 1,750 kDa. The density increased linearly with concentration and decreased with temperature. The data were fitted by the equation describing the density as a linear function of concentration and a quadratic function of temperature. The effect of molecular weight was negligible and thus single equation was sufficient to describe all data. The apparent and partial specific volumes were calculated from the density data including their extrapolated values to infinite dilutions. The measurement of ultrasound speed in the same solutions under the same conditions enabled to calculate the compressibility and its dependence on concentration and temperature. The compressibility decreased with both the concentration and the temperature but the effect of the concentration was only slight mild. The compressibility was used to estimate the hydration numbers which slightly decreased with increasing temperature and concentration. The addition of NaCl changed only the numerical values of density and ultrasound velocity while not changing the character of their dependence on temperature and concentration. Measured and calculated data indicate that hyaluronan does not disturb the specific water structure in the studied concentration range and support the idea of the existence of water clusters or nanodroplets hydrating the hyaluronan chains in solution. PMID:24721101

  12. [The influence of an isotonic solution containing benzalkonium chloride and a hypertonic seawater solution on the function of ciliary epithelium from the nasal cavity in vitro].

    PubMed

    Laberko, E L; Bogomil'sky, M R; Soldatsky, Yu L; Pogosova, I E

    2016-01-01

    The objective of the present study was to evaluate the influence of an isotonic saline solution containing benzalconium chloride and of a hypertonic seawater solution on the function of ciliary epithelium in the nasal cavity in vitro. To this effect, we investigated the cytological material obtained from 35 children presenting with adenoid tissue hypertrophy. The tissue samples were taken from the nasal cavity by the standard method. A cellular biopsy obtained from each patient was distributed between three tubes that contained isotonic saline solution supplemented by benzalconium chloride (0.1 mg/ml), a hypertonic seawater solution, and a standard physiological saline solution. It was shown that the number of the viable cells in both isotonic solutions was statistically comparable and significantly higher than in the hypertonic solution (p<0.05). The ciliary beat frequency of the cells embedded in the two isotonic solutions was not significantly different but considerably exceeded that in the hypertonic seawater solution (p<0.05). Thus, the present study has demonstrated the absence of the ciliotoxic influence of isotonic saline solution containing benzalconium chloride at a concentration of 0.1 mg/ml and the strong ciliotoxic effect of the hypertonic seawater solution. This finding gives reason to recommend isotonic solutions for the regular application whereas hypertonic solutions can be prescribed only during infectious and/or inflammatory ENT diseases. PMID:27213656

  13. A study on the re-solution heat treatment of AA 2618 aluminum alloy

    SciTech Connect

    Ozbek, Ibrahim . E-mail: iozbek@sakarya.edu.tr

    2007-03-15

    In the present study, the effects of re-solution treatment of AA2618 aluminum alloy has been investigated. Solution heat treatments of 520-640 deg. C for 14-24 h were applied followed by artificial aging. Characterization studies that were carried out by optical microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy techniques showed that recrystallisation was not observed by solution treatment at 530 deg. C whereas it did occur as the solution treatment and the duration time were increased above 530 deg. C. Increasing the solution treatment temperature further coarsened both the grains and the precipitates, resulting in significant reduction in hardness. Al{sub 9}FeNi-type intermetallics are not completely dissolved by these solution treatments.

  14. Cyclic stress effect on stress corrosion cracking of duplex stainless steel in chloride and caustic solutions

    NASA Astrophysics Data System (ADS)

    Yang, Di

    Duplex stainless steel (DSS) is a dual-phase material with approximately equal volume amount of austenite and ferrite. It has both great mechanical properties (good ductility and high tensile/fatigue strength) and excellent corrosion resistance due to the mixture of the two phases. Cyclic loadings with high stress level and low frequency are experienced by many structures. However, the existing study on corrosion fatigue (CF) study of various metallic materials has mainly concentrated on relatively high frequency range. No systematic study has been done to understand the ultra-low frequency (˜10-5 Hz) cyclic loading effect on stress corrosion cracking (SCC) of DSSs. In this study, the ultra-low frequency cyclic loading effect on SCC of DSS 2205 was studied in acidified sodium chloride and caustic white liquor (WL) solutions. The research work focused on the environmental effect on SCC of DSS 2205, the cyclic stress effect on strain accumulation behavior of DSS 2205, and the combined environmental and cyclic stress effect on the stress corrosion crack initiation of DSS 2205 in the above environments. Potentiodynamic polarization tests were performed to investigate the electrochemical behavior of DSS 2205 in acidic NaCl solution. Series of slow strain rate tests (SSRTs) at different applied potential values were conducted to reveal the optimum applied potential value for SCC to happen. Room temperature static and cyclic creep tests were performed in air to illustrate the strain accumulation effect of cyclic stresses. Test results showed that cyclic loading could enhance strain accumulation in DSS 2205 compared to static loading. Moreover, the strain accumulation behavior of DSS 2205 was found to be controlled by the two phases of DSS 2205 with different crystal structures. The B.C.C. ferrite phase enhanced strain accumulation due to extensive cross-slips of the dislocations, whereas the F.C.C. austenite phase resisted strain accumulation due to cyclic strain

  15. Process for producing gallium-containing solution from aluminum smelting dust

    SciTech Connect

    Ikeda, H.; Matsui, S.; Era, A.

    1988-02-16

    A process for producing a gallium-containing solution from aluminum smelting dust is described comprising mixing aluminum smelting dust with 5 to 50% by weight of an alkaline flux selected from the group consisting of sodium carbonate, sodium hydroxide, potassium carbonate, potassium hydroxide and mixtures thereof, heating the mixture to a temperature sufficient to roast the mixture without fusing the mixture, leaching the roasted mixture at a temperature of 80/sup 0/C. to 100/sup 0/C. with a mineral acid selected from the group consisting of sulfuric acid, hydrochloric acid, nitric acid and mixtures thereof to preferentially solubilize gallium from other material in the roasted mixture, and filtering the leached mixture to separate the solubilized gallium solution therefrom.

  16. Reentrant condensation of lysozyme: Implications for studying dynamics of lysozyme in aqueous solutions of lithium chloride

    SciTech Connect

    Mamontov, Eugene; O'Neill, Hugh Michael

    2014-01-01

    Recent studies have outlined the use of eutectic solution of lithium chloride in water to study microscopic dynamics of lysozyme in an aqueous solvent that is remarkably similar to pure water in many respects, yet allows experiments over a wide temperature range without the solvent crystallization. The eutectic point in (H2O)R(LiCl) system corresponds to R 7.3, and it is of interest to investigate whether less concentrated aqueous solutions of LiCl could be employed in low-temperature studies of a solvated protein. We have investigated a range of concentrations of lysozyme and LiCl in aqueous solutions to identify systems that do not show phase separation and avoid solvent crystallization on cooling down. Compared to the lysozyme concentration in solution, the concentration of LiCl in the aqueous solvent plays the major role in determining systems suitable for low-temperature studies. We have observed interesting and rich phase behavior reminiscent of reentrant condensation of proteins.

  17. Protection of copper surface with phytic acid against corrosion in chloride solution.

    PubMed

    Peca, Dunja; Pihlar, Boris; Ingrid, Milošev

    2014-01-01

    Phytic acid (inositol hexaphosphate) was tested as a corrosion inhibitor for copper in 3% sodium chloride. Phytic acid is a natural compound derived from plants, it is not toxic and can be considered as a green inhibitor. Electrochemical methods of linear polarization and potentiodynamic polarization were used to study the electrochemical behaviour and evaluate the inhibition effectiveness. To obtain the optimal corrosion protection the following experimental conditions were investigated: effect of surface pre-treatment (abrasion and three procedures of surface roughening), pre-formation of the layer of phytic acid, time of immersion and concentration of phytic acid. To evaluate the surface pre-treatment procedures the surface roughness and contact angle were measured. Optimal conditions for formation of phytic layer were selected resulting in the inhibition effectiveness of nearly 80%. Morphology and composition of the layer were further studied by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The layer of phytic acid with thickness in the nanometer range homogeneously covers the copper surface. The obtained results show that this natural compound can be used as a mildly effective corrosion inhibitor for copper in chloride solution. PMID:25286201

  18. Corrosion behavior of a superduplex stainless steel in chloride aqueous solution

    NASA Astrophysics Data System (ADS)

    Dabalà, Manuele; Calliari, Irene; Variola, Alessandra

    2004-04-01

    Super duplex stainless steels (SDSS) have been widely used as structural materials for chemical plants (especially in those engaged in phosphoric acid production), in the hydrometallurgy industries, and as materials for offshore applications due to their excellent corrosion resistance in chloride environments, compared with other commercial types of ferritic stainless steels. These alloys also possess superior weldability and better mechanical properties than austenitic stainless steels. However, due to their two-phase structure, the nature of which is very dependent on their composition and thermal history, the behavior of SDSS regarding localized corrosion appears difficult to predict, especially in chloride environments. To improve their final properties, the effect of the partition of the alloying elements between the two phases, and the composition and microstructure of each phase are the key to understanding the localized corrosion phenomena of SDSS. This paper concerns the effects of the SDSS microstructure and heat treatment on the SDSS corrosion resistance in aqueous solutions, containing different amounts of NaCl at room temperature.

  19. Interfacial behavior of perchlorate versus chloride ions in saturated aqueous salt solutions

    SciTech Connect

    Ghosal, S; Kuo, I W; Baer, M D; Bluhm, H

    2009-04-14

    In recent years combination of theoretical and experimental work have presented a novel view of the aqueous interface wherein hard and/or multiply charged ions are excluded from the interface, but large polarizable anions show interfacial enhancement relative to the bulk. The observed trend in the propensity of anions to adsorb at the air/water interface appears to be reverse of the Hofmeister series for anions. This study focuses on experimental and theoretical examination of the partitioning behavior of perchlorate (ClO{sub 4}{sup -}) and chloride (Cl{sup -}) ions at the air/water interface. We have used ambient pressure X-ray photoelectron spectroscopy technique to directly probe the interfacial concentrations of ClO{sub 4}{sup -} and Cl{sup -} ions in sodium perchlorate and sodium chloride solutions, respectively. Experimental observations are compared with first principles molecular dynamics simulations. Both experimental and simulation results show enhancement of ClO{sub 4}{sup -} ion at the interface, compared with the absence of such enhancement in the case of Cl{sup -} ion. These observations are in agreement with the expected trend in the interfacial propensity of anions based on the Hofmeister series.

  20. Leaching platinum-group metals in a sulfuric acid/chloride solution

    NASA Astrophysics Data System (ADS)

    Mahmoud, M. H. H.

    2003-04-01

    A leaching process was established based on the ability of platinum-group metals to form stable chloro-complexes in acidic chloride solutions. Industrial catalyst losses were examined for the recovery of platinum, palladium, and rhodium by leaching with a mixture of sulfuric acid and sodium chloride to avoid using aqua regia or autoclave conditions. Extraction of platinum and rhodium in 60% H2SO4 at 135°C steadily increased with increasing NaCl concentrations reaching 95% and 85%, respectively, at 0.1 M NaCl after two hours. By comparison, palladium was dissolved more quickly but also reached 85% under the same conditions. Extraction of each metal increased with temperatures up to 125°C but plateaued at higher temperatures. Similar behavior was observed with increasing H2SO4 concentrations up to 60%. More than 99% extraction of each metal was obtained after ten hours using 0.1 M NaCl and 60% H2SO4 at 125°C.

  1. A Novel Method for Investigating Solutions of Aluminum in Molten Cryolite

    NASA Astrophysics Data System (ADS)

    Dewing, Ernest W.; Jentoftsen, Trond E.; Lorentsen, Odd-Arne; Haarberg, Geir M.; Thonstad, Jomar

    2012-12-01

    In chronopotentiometric work on Fe2+ in a cryolite melt (Jentoftsen et al. in Metall. Mater. Trans. B, 2012, vol. 43B, pp. 869-74), after depletion of Fe2+ at the surface of the iron cathode was complete, continuing electrolysis produced a solution of Al in cryolite, provided that the time was less than a few hundred milliseconds. Potential-time curves indicate a diffusion-controlled, 2-electron reduction to form monovalent aluminum.

  2. Impact of aluminum chloride on process performance and microbial community structure of granular sludge in an upflow anaerobic sludge blanket reactor for natural rubber processing wastewater treatment.

    PubMed

    Thanh, Nguyen Thi; Watari, Takahiro; Thao, Tran Phuong; Hatamoto, Masashi; Tanikawa, Daisuke; Syutsubo, Kazuaki; Fukuda, Masao; Tan, Nguyen Minh; Anh, To Kim; Yamaguchi, Takashi; Huong, Nguyen Lan

    2016-01-01

    In this study, granular sludge formation was carried out using an aluminum chloride supplement in an upflow anaerobic sludge blanket (UASB) reactor treating natural rubber processing wastewater. Results show that during the first 75 days after the start-up of the UASB reactor with an organic loading rate (OLR) of 2.65 kg-COD·m(-3)·day(-1), it performed stably with a removal of 90% of the total chemical oxygen demand (COD) and sludge still remained in small dispersed flocs. However, after aluminum chloride was added at a concentration of 300 mg·L(-1) and the OLR range was increased up to 5.32 kg-COD·m(-3)·day(-1), the total COD removal efficiency rose to 96.5 ± 2.6%, with a methane recovery rate of 84.9 ± 13.4%, and the flocs began to form granules. Massively parallel 16S rRNA gene sequencing of the sludge retained in the UASB reactor showed that total sequence reads of Methanosaeta sp. and Methanosarcina sp., reported to be the key organisms for granulation, increased after 311 days of operation. This indicates that the microbial community structure of the retained sludge in the UASB reactor at the end of the experiment gave a good account of itself in not only COD removal, but also granule formation. PMID:27438256

  3. Generalized chloride mass balance: Forward and inverse solutions for one-dimensional tracer convection under transient flux

    SciTech Connect

    Ginn, T.R.; Murphy, E.M.

    1996-12-01

    Forward and inverse solutions are provided for analysis of inert tracer profiles resulting from one-dimensional convective transport under fluxes which vary with time and space separately. The developments are displayed as an extension of conventional chloride mass balance (CMB) techniques to account for transient as well as space-dependent water fluxes. The conventional chloride mass balance has been used over two decades to estimate recharge over large time scales in arid environments. In this mass balance approach, the chloride concentration in the pore water, originating from atmospheric fallout, is inversely proportional to the flux of water through the sediments. The CMB method is especially applicable to arid and semi-arid regions where evapotranspirative enrichment of the pore water produces a distinct chloride profile in the unsaturated zone. The solutions presented allow incorporation of transient fluxes and boundary conditions in CMB analysis, and allow analysis of tracer profile data which is not constant with depth below extraction zone in terms of a rational water transport model. A closed-form inverse solution is derived which shows uniqueness of model parameter and boundary condition (including paleoprecipitation) estimation, for the specified flow model. Recent expressions of the conventional chloride mass balance technique are derived from the general model presented here; the conventional CMB is shown to be fully compatible with this transient flow model and it requires the steady-state assumption on chloride mass deposition only (and not on water fluxes or boundary conditions). The solutions and results are demonstrated on chloride profile data from west central New Mexico.

  4. Production of aluminum metal by electrolysis of aluminum sulfide

    DOEpatents

    Minh, N.Q.; Loutfy, R.O.; Yao, N.P.

    1982-04-01

    Metallic aluminum may be produced by the electrolysis of Al/sub 2/S/sub 3/ at 700 to 800/sup 0/C in a chloride melt composed of one or more alkali metal chlorides, and one or more alkaline earth metal chlorides and/or aluminum chloride to provide improved operating characteristics of the process.

  5. Production of aluminum metal by electrolysis of aluminum sulfide

    DOEpatents

    Minh, Nguyen Q.; Loutfy, Raouf O.; Yao, Neng-Ping

    1984-01-01

    Production of metallic aluminum by the electrolysis of Al.sub.2 S.sub.3 at 700.degree.-800.degree. C. in a chloride melt composed of one or more alkali metal chlorides, and one or more alkaline earth metal chlorides and/or aluminum chloride to provide improved operating characteristics of the process.

  6. Solid solution barium-strontium chlorides with tunable ammonia desorption properties and superior storage capacity

    NASA Astrophysics Data System (ADS)

    Bialy, Agata; Jensen, Peter B.; Blanchard, Didier; Vegge, Tejs; Quaade, Ulrich J.

    2015-01-01

    Metal halide ammines are very attractive materials for ammonia absorption and storage-applications where the practically accessible or usable gravimetric and volumetric storage densities are of critical importance. Here we present, that by combining advanced computational materials prediction with spray drying and in situ thermogravimetric and structural characterization, we synthesize a range of new, stable barium-strontium chloride solid solutions with superior ammonia storage densities. By tuning the barium/strontium ratio, different crystallographic phases and compositions can be obtained with different ammonia ab- and desorption properties. In particular it is shown, that in the molar range of 35-50% barium and 65-50% strontium, stable materials can be produced with a practically usable ammonia density (both volumetric and gravimetric) that is higher than any of the pure metal halides, and with a practically accessible volumetric ammonia densities in excess of 99% of liquid ammonia.

  7. Kinetics of copper extraction from chloride solutions with model and commercial dialkyl pyridine-dicarboxylates

    SciTech Connect

    Cierpiszewski, R.

    2000-01-01

    The equilibrium and kinetics of copper(II) extraction from chloride solution with dioctyl pyridinedicarboxylate and commercial extractant ACORGA CLX-50 was studied. The measured dependencies show that the initial extraction rate and equilibrium constant strongly depend on the temperature and diluent for both extractants. The equilibrium and initial rate of extraction decrease as the temperature increases. The opposite effect of temperature is observed for dioctyl pyridine-2,4-dicarboxylate in homogeneous systems. In this case the rate of copper complexation increases as the temperature increases. The initial rate of reextraction increases as the temperature increases. Copper(II) is stripped from the complex with 0.1 M HCl with a rate significantly quicker for ACORGA CLX-50 in respect to dioctyl pyridine-2,4-dicarboxylate.

  8. Probing of local dissolution of Al-alloys in chloride solutions by AFM and SECM

    NASA Astrophysics Data System (ADS)

    Davoodi, A.; Pan, J.; Leygraf, C.; Norgren, S.

    2006-05-01

    Local dissolution of Al alloys was probed in situ in chloride solutions by using atomic force microscopy (AFM) and scanning electrochemical microscopy (SECM). Preferential dissolution in the boundary region between some intermetallic particles (IMPs) and alloy matrix, and trench formation around large IMPs during free immersion and under electrochemical anodic polarization were observed, which indicate different dissolution behavior associated to different types of IMPs. Moreover, by using an integrated AFM/SECM system with a dual mode cantilever/microelectrode probe, simultaneous probing of electrochemical active sites and topographic changes over the same area was performed with sub-micron resolution. This allowed the ongoing localized corrosion processes related to the IMP to be revealed.

  9. Models of the nearest surrounding of ions in aqueous solutions of dysprosium chloride

    NASA Astrophysics Data System (ADS)

    Smirnov, P. R.; Kritskii, I. L.; Grechin, O. V.

    2016-02-01

    Structural organization models are developed using radial distribution functions obtained earlier via XRD analysis for aqueous solutions of dysprosium chloride over a wide range of concentrations under standard conditions. The optimum variants are selected by calculating the theoretical functions for each model and comparing how they agree with experimental functions. Quantitative characteristics of the nearest surrounding of Dy3+ and Cl- ions, e.g., coordination numbers, interparticle distances, and varieties of ion pairs, are established. It is shown that the average number of water molecules in the first coordination sphere of a cation falls from 8.5 to 6 as the concentration grows; the structure of the system over the range of concentrations is determined by noncontact ion associates.

  10. Solid solution barium–strontium chlorides with tunable ammonia desorption properties and superior storage capacity

    SciTech Connect

    Bialy, Agata; Blanchard, Didier; Vegge, Tejs; Quaade, Ulrich J.

    2015-01-15

    Metal halide ammines are very attractive materials for ammonia absorption and storage—applications where the practically accessible or usable gravimetric and volumetric storage densities are of critical importance. Here we present, that by combining advanced computational materials prediction with spray drying and in situ thermogravimetric and structural characterization, we synthesize a range of new, stable barium-strontium chloride solid solutions with superior ammonia storage densities. By tuning the barium/strontium ratio, different crystallographic phases and compositions can be obtained with different ammonia ab- and desorption properties. In particular it is shown, that in the molar range of 35–50% barium and 65–50% strontium, stable materials can be produced with a practically usable ammonia density (both volumetric and gravimetric) that is higher than any of the pure metal halides, and with a practically accessible volumetric ammonia densities in excess of 99% of liquid ammonia. - Graphical abstract: Thermal desorption curves of ammonia from Ba{sub x}Sr{sub (1−x)}Cl{sub 2} mixtures with x equal to 0.125, 0.25 and 0.5 and atomic structure of Sr(NH{sub 3}){sub 8}Cl{sub 2}. - Highlights: • Solid solutions of strontium and barium chloride were synthesized by spray drying. • Adjusting molar ratios led to different crystallographic phases and compositions. • Different molar ratios led to different ammonia ab-/desorption properties. • 35–50 mol% BaCl{sub 2} in SrCl{sub 2} yields higher ammonia density than any other metal halide. • DFT calculations can be used to predict properties of the mixtures.

  11. Stability of the grain structure in 2219-O aluminum alloy friction stir welds during solution treatment

    SciTech Connect

    Chen, Y.C. . E-mail: armstrong@hit.edu.cn; Feng, J.C.; Liu, H.J.

    2007-02-15

    The stability of the grain structure in 2219-O aluminum alloy friction stir welds during solution treatment has been investigated. Experimental results show that the solution treatment causes drastic grain growth, Grain growth initiates at the surface and the bottom of the weld and then extends to the weld centre within several minutes. The solution treatment temperature and the welding heat input have a significant effect on grain growth. The higher the solution temperature, or the higher the welding heat input, the greater the grain growth. The instability of the grains is attributed to an imbalance between thermodynamic driving forces for grain growth and the pinning forces impeding grain boundary migration during solution treatment.

  12. Aluminum solute chemistry in stemflow in relation to season and tree species in a mid-Atlantic broadleaved deciduous forest

    NASA Astrophysics Data System (ADS)

    Levia, D. F.; Van Stan, J. T.; Inamdar, S. P.; Mitchell, M. J.; Scheick, C.; McHale, P.

    2011-12-01

    Aluminum toxicity is as serious concern in forest ecosystems. While much work has focused on soil solution aluminum chemistry in forests, less attention has been devoted to examining aluminum inputs from the canopy via washoff. Seasonality and the corresponding phenological conditions it triggers appears to have a detectable effect on aluminum washoff dynamics. In both leafed and leafless states, there is an intrastorm exponential decrease in aluminum inputs to forest soils. While aluminum fluxes were approximately threefold larger for American beech (Fagus grandifolia Ehrh.) in the leafless period compared to the leafed period, the opposite was true for yellow poplar (Liriodendron tulipifera L.) where leafless aluminum stemflow fluxes were half those of the leafed period. We attribute these differences to increased stemflow volumes in the leafless period for beech and the much more highly concentrated stemflow aluminum concentrations from yellow poplar during the leafed period. The Ca:Al ratio in stemflow inputs is of such a magnitude (ranging from approximately 5-80 for beech and 5-18 for yellow poplar) that it could ameliorate the lower Ca:Al ratio in the soil solution around the base of trees, thereby possibly buffering trees from some stress associated with aluminum release.

  13. Porous aluminum room temperature anodizing process in a fluorinated-oxalic acid solution

    NASA Astrophysics Data System (ADS)

    Dhahri, S.; Fazio, E.; Barreca, F.; Neri, F.; Ezzaouia, H.

    2016-08-01

    Anodizing of aluminum is used for producing porous insulating films suitable for different applications in electronics and microelectronics. Porous-type aluminum films are most simply realized by galvanostatic anodizing in aqueous acidic solutions. The improvement in application of anodizing technique is associated with a substantial reduction of the anodizing voltage at appropriate current densities as well as to the possibility to carry out the synthesis process at room temperature in order to obtain a self-planarizing dielectric material incorporated in array of super-narrow metal lines. In this work, the anodizing of aluminum to obtain porous oxide was carried out, at room temperature, on three different substrates (glass, stainless steel and aluminum), using an oxalic acid-based electrolyte with the addition of a relatively low amount of 0.4 % of HF. Different surface morphologies, from nearly spherical to larger porous nanostructures with smooth edges, were observed by means of scanning electron microscopy. These evidences are explained by considering the formation, transport and adsorption of the fluorine species which react with the Al3+ ions. The behavior is also influenced by the nature of the original substrate.

  14. Anticorrosive Solution of 6201 Aluminum Alloy used in STEG Company's Overhead Transmission Lines

    NASA Astrophysics Data System (ADS)

    Rhaiem, E.; Bouraoui, T.; Elhalouani, F.

    2010-11-01

    Nowadays, aluminum alloys are widely used as conductor in power electrical transmission lines mainly due to their good physicochemical and mechanical properties as well as their financial profitability. Nonetheless, aluminium alloys conductors, which normally fulfil standard requirements, can fail under severe service conditions in relationship with environmental factors such as humidity, industrial pollution or marine salts present in the atmosphere. In this case, an anticorrosive solution must be considered for an optimal use. This study reports the result of electrochemical polarization and scanning electron microscopy (SEM) on the corrosion inhibition of AA 6201 aluminum alloys exploited in High Electric conductors, using zincating deposition as inhibition. The electrochemical measurements of aluminum alloys after Zn coating of aluminum and varied immersion in 0.5M NaCl and in 0.5M NaCl + 0.1M Na2SO4 give a significant decrease in the corrosion current densities (icorr.), and an increase in corrosion potential (Ecorr). The thin film on the specimens has been proven by morphology study using SEM.

  15. A method of calculating quartz solubilities in aqueous sodium chloride solutions

    USGS Publications Warehouse

    Fournier, R.O.

    1983-01-01

    The aqueous silica species that form when quartz dissolves in water or saline solutions are hydrated. Therefore, the amount of quartz that will dissolve at a given temperature is influenced by the prevailing activity of water. Using a standard state in which there are 1,000 g of water (55.51 moles) per 1,000 cm3 of solution allows activity of water in a NaCl solution at high temperature to be closely approximated by the effective density of water, pe, in that solution, i.e. the product of the density of the NaCl solution times the weight fraction of water in the solution, corrected for the amount of water strongly bound to aqueous silica and Na+ as water of hydration. Generally, the hydration of water correction is negligible. The solubility of quartz in pure water is well known over a large temperature-pressure range. An empirical formula expresses that solubility in terms of temperature and density of water and thus takes care of activity coefficient and pressure-effect terms. Solubilities of quartz in NaCl solutions can be calculated by using that equation and substituting pe, for the density of pure water. Calculated and experimentally determined quartz solubilities in NaCl solutions show excellent agreement when the experiments were carried out in non-reactive platinum, gold, or gold plus titanium containers. Reactive metal containers generally yield dissolved silica concentrations higher than calculated, probably because of the formation of metal chlorides plus NaOH and H2. In the absence of NaOH there appears to be no detectable silica complexing in NaCl solutions, and the variation in quartz solubility with NaCl concentration at constant temperature can be accounted for entirely by variations in the activity of water. The average hydration number per molecule of dissolved SiO2 in liquid water and NaCl solutions decreases from about 2.4 at 200??C to about 2.1 at 350??C. This suggests that H4SiO4 may be the dominant aqueous silica species at 350??C, but other

  16. PROCESS OF ELECTROPLATING METALS WITH ALUMINUM

    DOEpatents

    Schickner, W.C.

    1960-04-26

    A process of electroplating aluminum on metals from a nonaqueous bath and a novel method of pretreating or conditioning the metal prior to electrodeposition of the aluminum are given. The process of this invention, as applied by way of example to the plating of uranium, comprises the steps of plating the uranium with the barrier inetal, immersing the barrier-coated uranium in fatty acid, and electrolyzing a water-free diethyl ether solution of aluminum chloride and lithium hydride while making the uranium the cathode until an aluminum deposit of the desired thickness has been formed. According to another preferred embodiment the barrier-coated uranium is immersed in an isopropyl alcohol solution of sterato chromic chloride prior to the fatty acid treatment of this invention.

  17. Influence of ionic strength on poly(diallyldimethylammonium chloride) macromolecule conformations in electrolyte solutions.

    PubMed

    Adamczyk, Zbigniew; Jamroży, Krzysztof; Batys, Piotr; Michna, Aneta

    2014-12-01

    Conformations of poly(diallyldimethylammonium chloride), PDADMAC, molecules in electrolyte solutions were experimentally evaluated by dynamic light scattering (DLS), micro-electrophoretic and viscosity measurements. The role of ionic strength varied within 10(-4) and 2M was systematically studied. The diffusion coefficient of the polymer molecules was equal to 1.3×10(-7)cm(2)s(-1) for the ionic strength range 5×10(-4) to 10(-2)M decreasing slightly for higher ionic strength. This corresponds to the hydrodynamic diameter of 38.5nm. Using the diffusion coefficient and the electrophoretic mobility data, the electrokinetic charge on PDADMAC molecules was calculated as a function of ionic strength. It was positive and varied between 84 and 51 elementary charges. This gives the effective ionization degree of the macromolecule equal to 13% and 8% for ionic strength of 5×10(-4) and 0.15M, respectively. Additional information about macromolecule conformation was derived from the viscosity measurements of dilute PDADMAC solutions. The intrinsic viscosity derived from these measurements decreased abruptly with ionic strength from 3400 for 10(-4)M to 100 for 2M, NaCl solutions. By extrapolating the hydrodynamic diameter and intrinsic viscosity data to zero ionic strength the polyelectrolyte molecule contour length of 240nm and the backbone diameter of 0.85nm were predicted. On the other hand, the decrease in the intrinsic viscosity for higher ionic strength was attributed to changes in macromolecule conformations to more collapsed ones. The experimental results were interpreted by molecular dynamics modeling of PDADMAC chain conformations in electrolyte solutions where the ionic strength effect and the effective ionization degree were considered. A quantitative agreement was attained for lower ionic strength range proving that the combined DLS and viscosity measurements furnish reliable information about macromolecule conformations in electrolyte solution. PMID:25265546

  18. A study of the electrochemical behavior in tungsten and caustic solutions and platinum/iridium in chloride solutions, informal report

    SciTech Connect

    Vitus, C.M.; Isaacs, H.S.; Schroeder, V.

    1994-11-22

    Platinum/iridium and tungsten wires were electronically etched in chloride and caustic solution, respectively, to produce tips with high aspect ratio. A direct relationship between the meniscus and the aspect ratio of etched tips was established. Scanning electron micrographs indicated that higher aspect ratios were obtained by changing the geometry of the meniscus during the etch either by an increase in the applied a.c. voltage or with the addition of a nonpolar layer above the electrolytic solution during the etching process. Above the breakdown voltage, two possible mechanisms appeared to control the etching process by expediting chemical dissolution: cavitation and sparking. Cavitation caused erosion due to the force of evolved gases against the electrode and sparking attacked the surface by vaporizing the metal. Sparking commenced on both wires near 24V. This voltage corresponded to a minimum in the plot of total etch time versus voltage. From light emission studies, sparking on Pt/Ir was associated with the ionization of Pt, Ir, Ca, and Cl. A compositional analysis of insoluble black particles produced during a.c. and d.c. etching of Pt/Ir revealed Pt and Ir as the major constituents of the product. The sparking process was shown to have a potential use in micromachining.

  19. Analysis of antibacterial efficacy of plasma-treated sodium chloride solutions

    NASA Astrophysics Data System (ADS)

    Hänsch, Mareike A. C.; Mann, Miriam; Weltmann, Klaus-Dieter; von Woedtke, Thomas

    2015-11-01

    In this study, the change of chemical composition of sodium chloride solutions (NaCl, 0.85%) induced by non-thermal atmospheric pressure plasma (APP) treatment and subsequent effects on bacteria (Escherichia coli) are investigated. Besides acidification caused by APP, hydrogen peroxide (H2O2), nitrite (\\text{NO}2- ), and nitrate (\\text{NO}3- ) are generated as stable end-products of various chemical reactions in APP-treated liquids. Inactivation kinetics and reduction factors were recorded for E. coli (K12). Almost identical antimicrobial effects were observed with both direct APP exposure to bacteria suspension and exposure of APP-treated liquids to bacteria (indirect treatment). Consequently, main bactericidal effects are caused by chemical reactions which are mediated via the liquid phase. Moreover, APP-treated liquids have shown long-term activity (30 min) that possibly correlates with the ratio of \\text{NO}2- /H2O2. Therefore, \\text{NO}2- and H2O2 are identified as key agents for antimicrobial short- and long-term effects, respectively. The antimicrobial stability observed is strongly dependent on the used treatment regime and correlates additionally with the altered chemical composition of APP-treated liquids. Besides these effects, it was also shown that bacteria do not acquire resistance to such APP-treated solutions.

  20. Study on kinetics of cathodic reduction of dissolved oxygen in 3.5% sodium chloride solution

    NASA Astrophysics Data System (ADS)

    Li, Yongjuan; Zhang, Dun; Wu, Jiajia

    2010-09-01

    Electrochemical reduction of dissolved oxygen in seawater on metals is of great importance for corrosion studies. The present paper studied cathodic reduction of dissolved oxygen on Q235 carbon steel in 3.5% sodium chloride (NaCl) solutions by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), rotating disk electrode (RDE) and rotating ring-disk electrode (RRDE). The cyclic voltammetric results demonstrated the cathodic process on Q235 carbon steel in O2-saturated 3.5% NaCl solution contains three reactions: dissolved oxygen reduction, iron oxides reduction and hydrogen evolution. The peak potential of oxygen reduction reaction (ORR) is -0.85 V vs Ag/AgCl, 3 molL-1 KCl. The EIS results indicated that the ORR occurring on Q235 carbon steel is a 4-electron process and that no finite diffusion is caused by the intermediate of H2O2 produced by ORR. The RDE and RRDE voltammograms confirmed the EIS results and it was found that the number of transferred electrons for ORR was nearly 4, i.e., dissolved oxygen reduced to water.

  1. Peptide-based biocoatings for corrosion protection of stainless steel biomaterial in a chloride solution.

    PubMed

    Muruve, Noah G G; Cheng, Y Frank; Feng, Yuanchao; Liu, Tao; Muruve, Daniel A; Hassett, Daniel J; Irvin, Randall T

    2016-11-01

    In this work, PEGylated D-amino acid K122-4 peptide (D-K122-4-PEG), derived from the type IV pilin of Pseudomonas aeruginosa, coated on 304 stainless steel was investigated for its corrosion resistant properties in a sodium chloride solution by various electrochemical measurements, surface characterization and molecular dynamics simulation. As a comparison, stainless steel electrodes coated with non-PEGylated D-amino acid retroinverso peptide (RI-K122-4) and D-amino acid K122-4 peptide (D-K122-4) were used as control variables during electrochemical tests. It was found that the D-K122-4-PEG coating is able to protect the stainless steel from corrosion in the solution. The RI-K122-4 coating shows corrosion resistant property and should be investigated further, while the D-K122-4 peptide coating, in contrast, shows little to no effect on corrosion. The morphological characterizations support the corrosion resistance of D-K122-4-PEG on stainless steel. The adsorption of D-K122-4 molecules occurs preferentially on Fe2O3, rather than Cr2O3, present on the stainless steel surface. PMID:27524070

  2. Extraction of copper(II) from acid chloride solutions by N-dodecyl- and N,N-dihexylpyridinecarboxamides

    SciTech Connect

    Borowiak-Resterna, A.

    1999-01-01

    N-dodecyl- and N,N-dihexylpyridinecarboxamides with amide group at 2, 3 or 4 position were synthesized. Model individual amides were used to recover copper(II) from chloride solutions at constant water activity and constant total concentration of dissolved species in aqueous solution. It was found, that pyridine-2-carboxamide forms with copper complexes (CuCl{sub 2}){sub x}(Ext){sub 2}. Remaining amides form with copper complexes CuCl{sub 2}(Ext){sub 2}. Monoalkylamides are not suitable for extraction because they and their complexes are slightly soluble in the hydrocarbon diluents. N,N-dialkylpyridinecarboxamides and their copper complexes are sufficiently soluble in the hydrocarbon phase to carry out extraction. However, they are strong extractants and extract efficiently copper already from dilute chloride solutions ([Cl{sup {minus}}] = 0.1 M). They extract also significant amounts of copper from concentrated (3--4 M) nitrate solutions.

  3. Catalytic destruction of perchlorate in ferric chloride and hydrochloric acid solution with control of temperature, pressure and chemical reagents

    DOEpatents

    Gu, Baohua; Cole, David R.; Brown, Gilbert M.

    2004-10-05

    A method is described to decompose perchlorate in a FeCl.sub.3 /HCl aqueous solution such as would be used to regenerate an anion exchange resin used to remove perchlorate. The solution is mixed with a reducing agent, preferably an organic alcohol and/or ferrous chloride, and can be heated to accelerate the decomposition of perchlorate. Lower temperatures may be employed if a catalyst is added.

  4. Specific features of the optical properties of potassium-aluminum borate glasses with copper chloride nanocrystals at high temperatures

    NASA Astrophysics Data System (ADS)

    Shirshnev, P. S.; Babkina, A. N.; Tsekhomskii, V. A.; Nikonorov, N. V.

    2015-09-01

    It is shown that heating of potassium-aluminum borate glasses with CuCl nanocrystals above 80°C leads to the disappearance of exciton absorption peaks, whereas cooling below 50°C gives rise to these peaks. These effects are related, respectively, to the melting of nanocrystals and crystallization of nanophase.

  5. Stability and corrosion resistance of superhydrophobic surface on oxidized aluminum in NaCl aqueous solution

    NASA Astrophysics Data System (ADS)

    Lv, Damei; Ou, Junfei; Xue, Mingshan; Wang, Fajun

    2015-04-01

    Superhydrophobic surface (SHS) was fabricated on aluminum via surface roughening by NaClO and surface passivation by hexadecyltrimethoxysilane. The long-term durability for storing the sample in air and the chemical stability for contacting the sample with NaCl solution were investigated. The short-term corrosion resistance for immersing the sample in NaCl solution for 1 h was investigated by potentiodynamic polarization, and the long-term corrosion resistance for immersing the sample in NaCl solution for 7 days was investigated by variation analyses on surface wettability, surface morphology, and surface chemistry. All experimental results suggested that the so-obtained SHS possessed good stability and good corrosion resistance under the testing conditions.

  6. Influence of Solute Content and Solidification Parameters on Grain Refinement of Aluminum Weld Metal

    NASA Astrophysics Data System (ADS)

    Schempp, Philipp; Cross, Carl Edward; Pittner, Andreas; Rethmeier, Michael

    2013-07-01

    Grain refinement provides an important possibility to enhance the mechanical properties ( e.g., strength and ductility) and the weldability (susceptibility to solidification cracking) of aluminum weld metal. In the current study, a filler metal consisting of aluminum base metal and different amounts of commercial grain refiner Al Ti5B1 was produced. The filler metal was then deposited in the base metal and fused in a GTA welding process. Additions of titanium and boron reduced the weld metal mean grain size considerably and resulted in a transition from columnar to equiaxed grain shape ( CET). In commercial pure aluminum (Alloy 1050A), the grain-refining efficiency was higher than that in the Al alloys 6082 and 5083. Different welding and solidification parameters influenced the grain size response only slightly. Furthermore, the observed grain-size reduction was analyzed by means of the undercooling parameter P and the growth restriction parameter Q, which revealed the influence of solute elements and nucleant particles on grain size.

  7. Preparation of alumina rods by electrospinning aluminum sec-butoxide/polyvinylpyrrolidone blended solutions.

    PubMed

    Choi, Jinho; Yoon, Yongho; Jung, Jihoon

    2013-09-01

    Aluminum sec-butoxide/polyvinylpyrrolidone (ASB/PVP) solutions, prepared by sol-gel processing of a mixture of ASB and PVP, were electrospun to form ASB/PVP organic-inorganic hybrid fibers. The diameter of alumina nanofibers was in the range of 200 nm to 500 nm. Since the fibers cracked after calcinations at 1100 degrees C, they were cured at 300 degrees C, 400 degrees C and 500 degrees C for 24 h each. The calcination of these composite fibers at temperatures above 1000 degrees C resulted in pure rod-shaped a-alumina. It was analyzed by SEM, TG-DTA, FTIR, and XRD. PMID:24205637

  8. Anodic dissolution and protection of aluminum alloy 7075 in hydroxide solutions

    SciTech Connect

    McCafferty, E.; Trzaskoma-Paulette, P.

    1997-03-01

    Dissolution of Al 7075 (UNS A97075) in sodium hydroxide (NaOH) solutions results in formation of a black, loosely adherent film of corrosion products that provides partial protection in the aqueous environment. Optical and scanning microscopy showed the reaction product film is a bilayer, with a thin, adherent inner layer and a thicker, more fragile outer layer. The reaction mechanism involves the dissolution of aluminum followed by formation of a precipitated film. Corrosion protection at moderate hydroxide concentrations is provided by the use of a partially fluorinated amino-surfactant or a silicon nitride (Si{sub 3}N{sub 4}) coating prepared by ion beam-assisted deposition.

  9. Atmospheric pitting corrosion of 304L stainless steel: the role of highly concentrated chloride solutions.

    PubMed

    Street, Steven R; Mi, Na; Cook, Angus J M C; Mohammed-Ali, Haval B; Guo, Liya; Rayment, Trevor; Davenport, Alison J

    2015-01-01

    The morphology of atmospheric pitting corrosion in 304L stainless steel plate was analysed using MgCl(2) droplets in relation to changes in relative humidity (RH) and chloride deposition density (CDD). It was found that highly reproducible morphologies occur that are distinct at different RH. Pitting at higher concentrations, i.e. lower RH, resulted in satellite pits forming around the perimeter of wide shallow dish regions. At higher RH, these satellite pits did not form and instead spiral attack into the shallow region was observed. Increasing CDD at saturation resulted in a very broad-mouthed pitting attack within the shallow dish region. Large data sets were used to find trends in pit size and morphology in what is essentially a heterogeneous alloy. Electrochemical experiments on 304 stainless steel wires in highly saturated solutions showed that the passive current density increased significantly above 3 M MgCl(2) and the breakdown pitting potential dropped as the concentration increased. It is proposed that the shallow dish regions grow via enhanced dissolution of the passive film, whereas satellite pits and a spiral attack take place with active dissolution of bare metal surfaces. PMID:25910020

  10. Aqueous solutions of didecyldimethylammonium chloride and octaethylene glycol monododecyl ether: Toward synergistic formulations against enveloped viruses.

    PubMed

    Nardello-Rataj, Véronique; Leclercq, Loïc

    2016-09-10

    Micellization of di-n-decyldimethylammonium chloride, [DiC10][Cl], and octaethylene glycol monododecyl ether, C12E8, mixtures have been investigated by surface tension and conductivity measurements. From these results, various physicochemical and thermodynamic key parameters (e.g. micellar mole fraction of [DiC10][Cl], interaction parameter, free energy of micellization, etc.) have been evaluated and discussed in detail. The results prove high synergistic effect between the two surfactants. Based on these results, the virucidal activity of an equimolar mixture of [DiC10][Cl] and C12E8 has been investigated. A marked synergism was observed on lipid-containing deoxyribonucleic and ribonucleic acid viruses, such as herpes virus, respiratory syncytial virus, and vaccinia viruses. In contrast, Coxsackievirus (non-enveloped virus) was not inactivated. These results support that the mechanism is based on the extraction of lipids and/or proteins from the envelope inside the mixed micelles. This extraction creates "holes" the size of which increases with concentration up to a specific value which triggers the virus inactivation. Such a mixture could be used to extend the spectrum of virucidal activity of the amphiphiles virucides commonly employed in numerous disinfectant solutions. PMID:27452423

  11. Corrosion of Alloy 625 in aqueous solutions containing chloride and oxygen

    SciTech Connect

    Kritzer, P.; Boukis, N.; Dinjus, E.

    1998-10-01

    Alloy 625 (UNS N06625) is used frequently as a reactor material for the oxidation of hazardous organic wastes in supercritical water (supercritical water oxidation [SCWO]). In the presence of chloride (Cl{sup {minus}}) and oxygen (O{sub 2}), all Ni-based alloys corrode fast in high-temperature, subcritical water. High-pressure, high-temperature-resistant tube reactors made of alloy 625 were used as specimens. Coupons were exposed simultaneously inside the test tubes. Experimental conditions included temperatures up to 500 C and pressures up to 38 MPa. Pitting corrosion was observed at temperatures above {approx}130 C to 215 C. At higher temperatures (up to the critical temperature of water), transpassive dissolution dominated. Under certain conditions, transgranular stress corrosion cracking (TGSCC) appeared in the transition zone between the passive and transpassive regions leading to premature failure of the test reactors. Parts of the corrosion products were insoluble in supercritical water and formed thick layers in the supercritical part of the reactor. Underneath these layers, very little intergranular corrosion (IGC) occurred. In neutral or alkaline solutions and in deaerated hydrochloric acid (HCl), corrosion rates of transpassive dissolution decreased drastically.

  12. Dialkyl pyridinedicarboxylates` extraction ability toward copper(II) from chloride solutions and its modification with alcohols

    SciTech Connect

    Bogacki, M.B.; Jakubiak, A.; Szymanowski, J.; Cote, G.

    1997-03-01

    Dipentyl pyridinedicarboxylates (denoted hereafter as L) with different positions of the ester groups were synthesized and used for copper(II) extraction from chloride solutions containing up to 10 mol/L Cl{sup {minus}}. The effect of decanol addition on copper extraction was studied. A molecular modeling technique was used to estimate the structures of extractants, copper complexes, and associates with alcohol. It was found that the ability of pyridinecarboxylates to extract copper depends on the aqueous phase composition and the position of the ester groups in the pyridine ring. All the investigated compounds except dipentyl pyridine-2,6-dicarboxylate extract copper(II) by formation of CuCl{sub 2}L{sub 2} complexes. Dipentyl pyridine-2,6-dicarboxylate forms another type of complex, probably CuCl{sub 2}L. However, this compound is not suitable for copper extraction as its copper complex precipitates. Dipentyl pyridine-3,5-dicarboxylate was found to be the most suitable extractant among the various compounds listed. Finally it is shown that the possibilities to modify the extraction ability of pyridinecarboxylates with a hydrophobic alcohol such as decanol are relatively weak. Some enhancement was, however, observed when 20% of decanol was added to the organic phase containing dipentyl pyridine-3,5-dicarboxylate.

  13. Electrochemical studies on a zinc-lead-cadmium alloy in aqueous ammonium chloride solution

    NASA Astrophysics Data System (ADS)

    Bhatt, D. P.; Udhayan, R.

    Studies are reported of the anodic polarization behaviour of a zinc-lead-cadmium alloy in aqueous ammonium chloride solution over a wide range of current densities between 5 and 1000 mA cm-2. A casting method is employed to prepare the electrode; the alloying constituents are analysed by atomic absorption spectroscopy (AAS). It is found that both the internal resistance and the anodic potential of the systems are at a minimum in 5.5 N NH 4Cl. The data has been compared with those obtained for pure zinc and it is concluded that the present alloy is a better electrode throughout the poplarization range of this investigation. A conventional weight-loss method shows that the corrosion rate is greater than that exhibited by pure zinc. Scanning electron micrographs of the post-immersed surface are compared with those for the pre-immersed surface. Supplementary investigations of linear polarization have been conducted in order to gain an understanding of the system for a narrow perturbation range of potential.

  14. Chloride Anions Regulate Kinetics but Not Voltage-Sensor Qmax of the Solute Carrier SLC26a5.

    PubMed

    Santos-Sacchi, Joseph; Song, Lei

    2016-06-01

    In general, SLC26 solute carriers serve to transport a variety of anions across biological membranes. However, prestin (SLC26a5) has evolved, now serving as a motor protein in outer hair cells (OHCs) of the mammalian inner ear and is required for cochlear amplification, a mechanical feedback mechanism to boost auditory performance. The mechanical activity of the OHC imparted by prestin is driven by voltage and controlled by anions, chiefly intracellular chloride. Current opinion is that chloride anions control the Boltzmann characteristics of the voltage sensor responsible for prestin activity, including Qmax, the total sensor charge moved within the membrane, and Vh, a measure of prestin's operating voltage range. Here, we show that standard narrow-band, high-frequency admittance measures of nonlinear capacitance (NLC), an alternate representation of the sensor's charge-voltage (Q-V) relationship, is inadequate for assessment of Qmax, an estimate of the sum of unitary charges contributed by all voltage sensors within the membrane. Prestin's slow transition rates and chloride-binding kinetics adversely influence these estimates, contributing to the prevalent concept that intracellular chloride level controls the quantity of sensor charge moved. By monitoring charge movement across frequency, using measures of multifrequency admittance, expanded displacement current integration, and OHC electromotility, we find that chloride influences prestin kinetics, thereby controlling charge magnitude at any particular frequency of interrogation. Importantly, however, this chloride dependence vanishes as frequency decreases, with Qmax asymptoting at a level irrespective of the chloride level. These data indicate that prestin activity is significantly low-pass in the frequency domain, with important implications for cochlear amplification. We also note that the occurrence of voltage-dependent charge movements in other SLC26 family members may be hidden by inadequate

  15. Neutron Diffraction of Aqueous Tetramethylammonium Chloride (TMA) Solutions and TMA Intercalated Swelling Clays Under Burial Conditions

    NASA Astrophysics Data System (ADS)

    Patel, R.; Howard, C. A.; Greenwell, C.; Youngs, T.; Soper, A. K.; Skipper, N. T.

    2014-12-01

    There is a need for the improvement and optimisation of clay swelling inhibitors for the enhancement of oil and gas exploration. The hydration region of both ions and the possibility of ion pairing in 1 molar aqueous solution of clay swelling inhibitor, tetramethylammonium chloride (TMACl), in D2O, under elevated hydrostatic-pressures and temperatures has been determined with unprecedented detail using a combination of neutron diffraction and small-angle scattering in conjunction with hydrogen/deuterium isotopic labeling. The O-H correlation function (H-bonds) for the water in the 1.0M solution is measured and compared with that for pure D2O. Also investigated is the effect of burial conditions on the d-spacing of TMA-intercalated vermiculite. Contrary to expectations, no aggregation of TMA ions due to hydrophobic interactions is observed, nor are any ionic pairs of TMA+ and Cl- at these burial conditions. The data revealed a more ordered water-water structure with the addition of TMACl from bulk D2O. There is no change in the hydration structure measured at the applied elevated conditions. This is in remarkable contrast to pure water at the same conditions which is well known to be compressible. The dry d-spacing of the TMA-exchanged Eucatex vermiculite is measured at 13.66 Å which increases to 14.03 Å with the addition of D2O. Beyond this, there is no change in d-spacing with increasing pressure and temperature indicating the strength of the TMA ions binding to the clay interlayers and therefore its performance as a clay-swelling inhibitor.

  16. Effects of aluminum chloride on sodium current, transient outward potassium current and delayed rectifier potassium current in acutely isolated rat hippocampal CA1 neurons.

    PubMed

    Zhang, Bo; Nie, Aifang; Bai, Wei; Meng, Ziqiang

    2004-09-01

    The effects of aluminum chloride (AlCl3) on sodium current (INa), the transient outward potassium (IA) and delayed rectifier potassium currents (IK) in hippocampal CA1 neurons of rats were studied using the whole cell patch-clamp technique. AlCl3 decreased INa, IA, and IK in a partly reversible, dose and voltage-dependent manner. AlCl3 prolonged the time to peak of INa, and increased the inactivation time constants of INa and IA . In addition, 1000 microM AlCl3 shifted the voltage dependence of steady-state activation of INa, IA and IK toward positive potential, and the voltage dependence of steady-state inactivation of INa, IA toward negative potential. These results imply that AlCl3 could affect the activation and inactivation courses of sodium current and potassium current of rat hippocampal CA1 neurons, which may contribute to damage of the central nervous system by aluminum. PMID:15234075

  17. NEUTRALIZATIONS OF HIGH ALUMINUM LOW URANIUM USED NUCLEAR FUEL SOLUTIONS CONTAINING GADOLINIUM AS A NEUTRON POISON

    SciTech Connect

    Taylor-Pashow, K.

    2011-06-08

    H-Canyon will begin dissolving High Aluminum - Low Uranium (High Al/Low U) Used Nuclear Fuel (UNF) following approval by DOE which is anticipated in CY2011. High Al/Low U is an aluminum/enriched uranium UNF with small quantities of uranium relative to aluminum. The maximum enrichment level expected is 93% {sup 235}U. The High Al/Low U UNF will be dissolved in H-Canyon in a nitric acid/mercury/gadolinium solution. The resulting solution will be neutralized and transferred to Tank 39H in the Tank Farm. To confirm that the solution generated could be poisoned with Gd, neutralized, and discarded to the Savannah River Site (SRS) high level waste (HLW) system without undue nuclear safety concerns the caustic precipitation of simulant solutions was examined. Experiments were performed with three simulant solutions representative of the H-Canyon estimated concentrations in the final solutions after dissolution. The maximum U, Gd, and Al concentration were selected for testing from the range of solution compositions provided. Simulants were prepared in three different nitric acid concentrations, ranging from 0.5 to 1.5 M. The simulant solutions were neutralized to four different endpoints: (1) just before a solid phase was formed (pH 3.5-4), (2) the point where a solid phase was obtained, (3) 0.8 M free hydroxide, and (4) 1.2 M free hydroxide, using 50 wt % sodium hydroxide (NaOH). The settling behavior of the neutralized solutions was found to be slower compared to previous studies, with settling continuing over a one week period. Due to the high concentration of Al in these solutions, precipitation of solids was observed immediately upon addition of NaOH. Precipitation continued as additional NaOH was added, reaching a point where the mixture becomes almost completely solid due to the large amount of precipitate. As additional NaOH was added, some of the precipitate began to redissolve, and the solutions neutralized to the final two endpoints mixed easily and had expected

  18. The anodizing behavior of aluminum in malonic acid solution and morphology of the anodic films

    NASA Astrophysics Data System (ADS)

    Ren, Jianjun; Zuo, Yu

    2012-11-01

    The anodizing behavior of aluminum in malonic acid solution and morphology of the anodic films were studied. The voltage-time response for galvanostatic anodization of aluminum in malonic acid solution exhibits a conventional three-stage feature but the formation voltage is much higher. With the increase of electrolyte concentration, the electrolyte viscosity increases simultaneously and the high viscosity decreases the film growth rate. With the concentration increase of the malonic acid electrolyte, the critical current density that initiates local "burning" on the sample surface decreases. For malonic acid anodization, the field-assisted dissolution on the oxide surface is relatively weak and the nucleation of pores is more difficult, which results in greater barrier layer thickness and larger cell dimension. The embryo of the porous structure of anodic film has been created within the linear region of the first transient stage, and the definite porous structure has been established before the end of the first transient stage. The self-ordering behavior of the porous film is influenced by the electrolyte concentration, film thickness and the applied current density. Great current density not only improves the cell arrangement order but also brings about larger cell dimension.

  19. Inhibition of Corrosion of 3003 Aluminum Alloy in Ethylene Glycol-Water Solutions

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Cheng, Y. F.

    2011-03-01

    In this study, the inhibiting effects of four types of inhibitors, including gluconate, cinnamate, molybdate, and nitrate, on corrosion of a 3003 aluminum (Al) alloy were investigated in ethylene glycol-water solutions that simulate the automotive coolant by various electrochemical measurements. It was found that the tested inhibitors were effective to inhibit corrosion of 3003 Al alloy under both static and turbulent flow conditions. They all behave as anodic inhibitors, which inhibit the Al alloy corrosion by passivating Al alloy and decreasing its anodic current density. A turbulent flow of the solution decreases the corrosion resistance of Al alloy and the inhibiting effect of the inhibitors. The inhibiting effect of the inhibitors is ranked as: nitrate > cinnamate > gluconate > molybdate.

  20. Separation of Ce and La from Synthetic Chloride Leach Solution of Monazite Sand by Precipitation and Solvent Extraction

    NASA Astrophysics Data System (ADS)

    Banda, Raju; Jeon, Ho Seok; Lee, Man Seung

    2014-12-01

    Precipitation and solvent extraction experiments have been performed to recover light rare earths from simulated monazite sand chloride leach solutions. Precipitation conditions were obtained to recover Ce by adding NaClO as an oxidant. Among some cationic extractants (PC 88A, D2EHPA, Cyanex 272, LIX 63), PC 88A showed the best performance to separate La from the resulting chloride solution. Furthermore, the mixture of PC 88A with other solvating (TBP, TOPO) and amine extractants (Alamine 336, Aliquat 336) was tested to increase the separation factor of La from Pr and Nd. The use of mixed extractants greatly enhanced the separation of La from the two other metals. McCabe-Thiele diagrams for the extraction of Pr and Nd with the PC 88A/Alamine 336 mixture were constructed.

  1. Structure and corrosive wear resistance of plasma-nitrided alloy steels in 3% sodium chloride solutions

    SciTech Connect

    Lee, C.K.; Shih, H.C. . Dept. of Materials Science and Engineering)

    1994-11-01

    Type 304 stainless steel (SS), type 410 SS, and type 4140 low-alloy steel were plasma nitrided in a commercial furnace at 560 C for 50 h. Microstructure and the composition of the nitrided layer were analyzed. The resistance to corrosive wear was evaluated by a tribotest in which the specimen was held under potentiostatic control at anodic and cathodic potentials in 3% sodium chloride solution (pH 6.8). Electrochemical polarization measurements were made, and the surface morphology and composition after corrosive wear were examined. Wear rates at cathodic potentials were very low, but significant weight losses were observed as the applied potentials were increased anodically. The coefficient of friction varied in a fashion similar to the wear rate. For the untreated alloys, the magnitude of the wear rate and coefficient of friction decreased as follows: type 4140 alloy > type 41 SS > type 304 SS. For the plasma-nitrided alloys, the ranking was: type 304 SS > type 410 SS. type 4140 alloy. Plasma nitriding was shown to be beneficial to the corrosive wear resistance of type 4140 alloy, but an adverse effect was obtained for types 304 and 410 SS. These findings could be interpreted in terms of the electrochemical polarization characteristics of a static specimen and were strongly related to the subtleties of the nitrided microstructures. The stable chromium nitride (CrN) segregated in the [gamma]-iron (type 304 SS) and [alpha]-Fe (type 41 SS) matrices and resulted in a pitting and spalling type of corrosive wear mechanism. The phases [epsilon]-(Fe, Cr)[sub 2-3]N and [gamma]-(Fe, Cr)[sub 4]N enriched in the surface layer of nitrided type 4140 alloy provided excellent corrosive wear resistance.

  2. Corrosion Mitigation of Copper in Acidic Chloride Pickling Solutions by 2-Amino-5-ethyl-1,3,4-thiadiazole

    NASA Astrophysics Data System (ADS)

    Sherif, El-Sayed M.

    2010-08-01

    Corrosion of copper in acidic chloride pickling solutions of 0.5 M HCl and its mitigation by 2-amino-5-ethyl-1,3,4-thiadiazole (AETDA) have been investigated using potentiodynamic polarization, chronoamperometry, electrochemical impedance spectroscopy (EIS), and weight-loss measurements. The study was also complemented by scanning electron microscopy (SEM), energy dispersive x-ray (EDX), and UV-Visible absorption spectroscopy investigations. The presence of AETDA and the increase of its concentration in the chloride solutions greatly decreased the corrosion rate and increased the surface and polarization resistances of copper as indicated by the electrochemical measurements. Weight-loss data also indicated that AETDA decreases the dissolution of copper coupons in the studied chloride solution. SEM/EDX investigations showed that AETDA molecules are strongly adsorbed onto copper surface. The UV-Visible absorption spectra confirmed that AETDA molecules suppress the corrosion of copper via their interactions with the copper surface via their adsorption then formation of AETDA-Cu complex.

  3. Effect of Organic Acid Additions on the General and Localized Corrosion Susceptibility of Alloy 22 in Chloride Solutions

    SciTech Connect

    Carranza, R M; Giordano, C M; Rodr?guez, M A; Ilevbare, G O; Rebak, R B

    2007-08-28

    Electrochemical studies such as cyclic potentiodynamic polarization (CPP) and electrochemical impedance spectroscopy (EIS) were performed to determine the corrosion behavior of Alloy 22 (N06022) in 1M NaCl solutions at various pH values from acidic to neutral at 90 C. All the tested material was wrought Mill Annealed (MA). Tests were also performed in NaCl solutions containing weak organic acids such as oxalic, acetic, citric and picric. Results show that the corrosion rate of Alloy 22 was significantly higher in solutions containing oxalic acid than in solutions of pure NaCl at the same pH. Citric and picric acids showed a slightly higher corrosion rate, and acetic acid maintained the corrosion rate of pure chloride solutions at the same pH. Organic acids revealed to be weak inhibitors for crevice corrosion. Higher concentration ratios, compared to nitrate ions, were needed to completely inhibit crevice corrosion in chloride solutions. Results are discussed considering acid dissociation constants, buffer capacity and complex formation constants of the different weak acids.

  4. Solution Equilibria between Aluminum(III) Ion and L-histidine or L-tyrosine

    PubMed Central

    Jelic, Ratomir; Dzajevic, Dragana; Cvijovic, Mirjana

    2002-01-01

    Toxic effects due to high aluminum body loads were observed in a number of conditions following ingestion of Al-containing antacids. Bio-availability of aluminum depends not only on the solubility of the ingested salt but also on the physico-chemical properties of the soluble Al complexes formed in body fluids. Amino acids may, upon interaction with Al-salts, form absorbable Al-complexes. Hence, complex formation equilibria between Al3+ and either, L- histidine or L-tyrosine were studied by glass electrode potentiometric (0.1 mol/L LiCl ionic medium, 298 K), proton NMR and uv spectrophotometric measurements. Non linear least squares treatment of the potentiometric data indicates that in the concentration ranges: 0.5≤CA1≤2.0 ; 1.0≤CHis≤10.0; 2.5≤PH≤6.5, in Al3+ + His solutions, the following complexes (with log overall stability constants given in parenthesis) are formed: Al(HHis)3+(12.21±0.08); Al(His)2+, (7.25±0.08); and Al(HHis)His2+, (20.3±0.1). In Al3+ + Tyr solutions in the concentration range 1.0≤CTyr≤3.0 mmol/L and ligand to metal concentration ratio from 2:1 to 3:1, in the pH interval from 3.0 to 6.5 the formation of the following complexes was detected: Al(HTyr)2+, (12.72±0.09); Al(Tyr)2+, (10.16±0.03) and Al(OH)2Tyr , (2.70±0.05). Proton NMR data indicate that in Al(His)2+ complex histidine acts as a monodentate ligand but its bidentate coordination is possible with carboxylate oxygen and imidazole 1-nitrogen as donors. In Al(HTyr)3+ complex tyrosine is a monodentate ligand with carboxylate oxygen as donor. The mechanism of the formation of complexes in solution is discussed as well as their possible role in aluminum toxicity. PMID:18476000

  5. Anodic behavior of aluminum current collector in LiTFSI solutions with different solvent compositions

    NASA Astrophysics Data System (ADS)

    Morita, Masayuki; Shibata, Takuo; Yoshimoto, Nobuko; Ishikawa, Masashi

    The anodic behavior of aluminum (Al) current collector of Li-ion batteries has been investigated in organic electrolyte solutions containing lithium bis[trifluoromethylsulfonyl]imide (Li(CF 3SO 2) 2N: LiTFSI) with different compositions of solvents. The Al anode was subjected to anodic corrosion in the LiTFSI solution, but the degree of the corrosion depended on the solvent composition. The surface of Al pre-treated by mechanical polishing has suffered serious corrosion in the mixed solvent solution of ethylene carbonate (EC) and dimethyl carbonate (DMC), whereas the Al surface pre-treated by electro-polishing was relatively stable in the mixed solvent of γ-butyrolactone (GBL) and DMC. The results of electrochemical quartz crystal microbalance (EQCM) experiments showed that the mass change of the Al surface during the potential cycling in GBL + DMC was much different from that in the EC + DMC solution. Scanning electron microscope (SEM) observation proved that the corrosion pits evolved on the electro-polished Al surface after potential cycling, but GBL resulted in a smaller amount of the corrosion product on the Al surface.

  6. Study of the uptake by duckweed of aluminum, copper, and lead from aqueous solution

    SciTech Connect

    Mo, S.C.; Choi, D.S.; Robinson, J.W.

    1988-01-01

    THE UPTAKE OF AL/sup 3 +/, CU/sup 2 +/, AND PB/sup 2 +/ FROM AQUEOUS SOLUTION BY DUCKWEED HAS BEEN OBSERVED AT PH 4.0, 4.5, AND 5.0. THE RESULTS SHOWED THAT THE UPTAKE OF PB/sup 2 +/ WAS MUCH FASTER THAN AL/sup 3 +/ AND CU/sup 2 +/. THE UPTAKE OF CU/sup 2 +/ WAS SUPPRESSED BY THE PRESENCE OF PB/sup 2 +/ AND AL/sup 3 +/. THE PROPORTION OF METAL UPTAKE (PMUT) BY DUCKWEED WAS DEPENDENT ON THE METAL CONCENTRATION IN THE SOLUTION WHEN ONLY ONE KIND OF METAL ION WAS PRESENT. IT WAS DECREASED BY INCREASING CONCENTRATIONS OF OTHER METALS IN MIXTURES OF SOLUTIONS. THE METAL UPTAKE BY THE DUCKWEED WAS ALWAYS LESS THAN THE LOSS OF METAL CONTENT IN THE RELEVANT SOLUTION. THIS FACT IMPLIED THAT THE PROCESS OF THE UPTAKE OF METAL IONS BY THE DUCKWEED MAY INVOLVE TWO STAGES. IN THE FIRST, THE METAL IS ABSORBED BUT THEN LATER IT IS ADSORBED BY THE DUCKWEED. THE ALUMINUM ION WAS FOUND TO BE MORE TOXIC THAN THE COPPER ION AT LOWER PH AND HIGHER CONCENTRATION, BUT THE SITUATION IS REVERSED AT HIGHER PH. A POSSIBLE EXPLANATION OF TOXICITY OF CU/sup 2 +/ AND AL/sup 3 +/ IN CHLOROPHYLL WAS REPLACED BY THE CU/sup 2 +/ OR AL/sup 3 +/. THIS MAY LEAD THE CHLOROPHYLL TO LOSE ITS NORMAL ACTIVITY AND KILL THE DUCKWEED.

  7. Dual blockade of the A1 and A2A adenosine receptor prevents amyloid beta toxicity in neuroblastoma cells exposed to aluminum chloride.

    PubMed

    Giunta, Salvatore; Andriolo, Violetta; Castorina, Alessandro

    2014-09-01

    In a previous work we have shown that exposure to aluminum (Al) chloride (AlCl3) enhanced the neurotoxicity of the amyloid beta(25-35) fragment (Abeta(25-35)) in neuroblastoma cells and affected the expression of Alzheimer's disease (AD)-related genes. Caffein, a compound endowed with beneficial effects against AD, exerts neuroprotection primarily through its antagonist activity on A2A adenosine receptors (A2AR), although it also inhibits A1Rs with similar potency. Still, studies on the specific involvement of these receptors in neuroprotection in a model of combined neurotoxicity (Abeta(25-35)+AlCl3) are missing. To address this issue, cultured SH-SY5Y cells exposed to Abeta(25-35)+AlCl3 were assessed for cell viability, morphology, intracellular ROS activity and expression of apoptosis-, stress- and AD-related proteins. To define the role of A1R and A2ARs, pretreatment with caffein, specific receptor antagonists (DPCPX or SCH58261) or siRNA-mediated gene knockdown were delivered. Results indicate that AlCl3 treatment exacerbated Abeta(25-35) toxicity, increased ROS production, lipid peroxidation, β-secretase-1 (BACE1) and amyloid precursor protein (APP). Interestingly, SCH58261 successfully prevented toxicity associated to Abeta(25-35) only, whereas pretreatment with both DPCPX and SCH58261 was required to fully avert Abeta(25-35)+AlCl3-induced damage, suggesting that A1Rs might also be critically involved in protection during combined toxicity. The effects of caffein were mimicked by both N-acetyl cysteine, an antioxidant, and desferrioxamine, likely acting through distinct mechanisms. Altogether, our data establish a novel protective function associated with A1R inhibition in the setting of combined Abeta(25-35)+AlCl3 neurotoxicity, and expand our current knowledge on the potential beneficial role of caffein to prevent AD progression in subjects environmentally exposed to aluminum. PMID:25058312

  8. Solubility of hydrogen sulfide in aqueous solutions of the single salts sodium sulfate, ammonium sulfate, sodium chloride, and ammonium chloride at temperatures from 313 to 393 K and total pressures up to 10 MPa

    SciTech Connect

    Xia, J.; Kamps, A.P.S.; Rumpf, B.; Maurer, G.

    2000-04-01

    New experimental results for the solubility of hydrogen sulfide in aqueous solutions of the single salts sodium sulfate, ammonium sulfate, sodium chloride, and ammonium chloride at temperatures from 313 to 393 K and total pressures up to 10 MPa are reported. As in the salt-free system, a second-hydrogen sulfide-rich--liquid phase is observed at high hydrogen sulfide concentrations. A model to describe the phase equilibrium is presented. Calculations are compared to the new experimental data.

  9. Effect of benzalkonium chloride-free latanoprost ophthalmic solution on ocular surface in patients with glaucoma

    PubMed Central

    Walimbe, Tejaswini; Chelerkar, Vidya; Bhagat, Purvi; Joshi, Abhijeet; Raut, Atul

    2016-01-01

    Introduction Benzalkonium chloride (BAK), included as a preservative in many topical treatments for glaucoma, induces significant toxicity and alters tear breakup time (TBUT). BAK-containing latanoprost, an ester prodrug of prostaglandin F2α, can cause ocular adverse events (AEs) associated with BAK. The purpose of this study was to evaluate the efficacy and safety of BAK-free latanoprost. Patients and methods A prospective, open-label, single-arm, multicenter, 8-week study in patients with primary open-angle glaucoma or ocular hypertension taking BAK-containing latanoprost for ≥12 months was performed. Patients were switched to BAK-free latanoprost ophthalmic solution 0.005% administered once daily, and eyes were assessed after 28 and 56 days. Primary efficacy and safety variables were TBUT and treatment-emergent AEs, respectively. Results At day 56, 40 eyes were evaluable. Mean TBUT increased significantly from baseline (3.67±1.60 seconds) to 5.03±2.64 and 6.06±3.39 seconds after 28 and 56 days of treatment with BAK-free latanoprost (P<0.0001). Ocular Surface Disease Index© (OSDI©) score also decreased significantly to 12.06±13.40 and 7.06±10.75 at 28 and 56 days, respectively, versus baseline (18.09±18.61, P<0.0001). In addition, inferior corneal staining score decreased significantly to 0.53 from baseline (0.85, P=0.0033). A reduction in conjunctival hyperemia and intraocular pressure was observed at both time points. No treatment-related serious AEs were evident and 12 (26.08%) treatment-emergent AEs occurred in seven patients, with eye pain and irritation being the most frequent. No clinically significant changes in vital signs or slit lamp examinations were observed. Conclusion Results indicate that switching from BAK-containing latanoprost to BAK-free latanoprost resulted in significant improvements in TBUT, OSDI© score, and inferior corneal staining score, and measurable reductions in conjunctival hyperemia score. Furthermore, BAK

  10. [sup 31]P and [sup 27]Al NMR investigations of the effects of pH on aqueous solutions containing aluminum and phosphorus

    SciTech Connect

    Mortlock, R.F.; Bell, A.T.; Radke, C.J. Univ. of California, Berkeley )

    1993-01-21

    [sup 31]P and [sup 27]Al NMR spectroscopies are used to characterize the distribution of soluble aluminophosphate species in aqueous solutions of tetramethylammonium (TMA) hydroxide, phosphoric acid, and aluminum chloride. Solution compositions range from 0.1 to 1 mol % P, P/Al = 0.1-5, P/(TMA)[sub 2]O = 0.37-10. For solutions of 1 mol % P, a phase diagram is constructed for various concentrations of TMAOH and Al. The phase diagram is divided into three regions: a high-pH region (pH [ge] 6), a medium-pH range (2 [le] pH [le] 10) in which stable solid phases exist, and a low-pH region (pH [le] 2). In the low-pH region, soluble aluminophosphate complexes form between P species (H[sub 3]PO[sub 4] acid dimers, H[sub 3]PO[sub 4] molecules, and H[sub 2]PO[sub 4][sup [minus

  11. Recovery of acids and sodium hydroxide from solutions of sodium sulfate and sodium chloride with the use of bipolar membranes

    SciTech Connect

    Bobrinskaya, G.A.; Pavlova, T.V.; Shatalov, A.Ya.

    1985-09-01

    The authors examined the kinetic laws governing the electrodialysis recovery of hydrochloric acid and sulfuric acid, as well as sodium hydroxide, from 1M sodium chloride and 0.5 M sodium sulfate solutions and from a mixture of these salts with the use of the MB-1, MB-2, and MB-3 bipolar membranes. Kinetic plots of the current density and the concentration of the acid and the base in the chambers next to the bipolar membranes during the electrodialysis treatment of 1M sodium chloride, 0.5 M sodium sulfate, and solutions are presented. It was established that it is better to use the MB-3 membrane for the electrodialysis conversion of sodium chloride and sodium sulfate into acids and sodium hydroxide owing to the high rate and current efficiency and low expenditure of electrical energy and degree of contamination of the products obtained by the salts. It was also established that the resistance of the MB-1 and MB-2 bipolar membranes is almost an order of magnitude higher than that of the MB-3 membrane.

  12. Anodic behavior of alloys in the systems aluminum-scandium(yttrium, praseodymium, neodymium) in a neutral medium

    SciTech Connect

    Ganiev, I.N.; Yunusov, I.; Krasnoyarskii, V.V.

    1988-03-10

    The authors investigated the influence of scandium, yttrium, praseodymium, and neodymium on the anodic behavior of aluminum in a 3% sodium chloride solution by a potentiodynamic method which provided information over a time interval during which the state of the electrode surface and the composition of the solution remained essentially unchanged. Data were derived for electrochemical and pitting corrosion for different alloy contents and compositions. Results were analyzed for aluminum-scandium, aluminum-yttrium, aluminum-praseodymium, and aluminum-neodymium binary systems.

  13. Effects of temperature and pressure on stress corrosion cracking behavior of 310S stainless steel in chloride solution

    NASA Astrophysics Data System (ADS)

    Zhong, Yunpan; Zhou, Cheng; Chen, Songying; Wang, Ruiyan

    2016-06-01

    310S is an austenitic stainless steel for high temperature applications, having strong resistance of oxidation, hydrogen embrittlement and corrosion. Stress corrosion cracking(SCC) is the main corrosion failure mode for 310S stainless steel. Past researched about SCC of 310S primarily focus on the corrosion mechanism and influence of temperature and corrosive media, but few studies concern the combined influence of temperature, pressure and chloride. For a better understanding of temperature and pressure's effects on SCC of 310S stainless steel, prepared samples are investigated via slow strain rate tensile test(SSRT) in different temperature and pressure in NACE A solution. The result shows that the SCC sensibility indexes of 310S stainless steel increase with the rise of temperature and reach maximum at 10MPa and 160°C, increasing by 22.3% compared with that at 10 MPa and 80 °C. Instead, the sensibility decreases with the pressure up. Besides, the fractures begin to transform from the ductile fracture to the brittle fracture with the increase of temperature. 310S stainless steel has an obvious tendency of stress corrosion at 10MPa and 160°C and the fracture surface exists cleavage steps, river patterns and some local secondary cracks, having obvious brittle fracture characteristics. The SCC cracks initiate from inclusions and tiny pits in the matrix and propagate into the matrix along the cross section gradually until rupture. In particular, the oxygen and chloride play an important role on the SCC of 310S stainless steel in NACE A solution. The chloride damages passivating film, causing pitting corrosion, concentrating in the cracks and accelerated SSC ultimately. The research reveals the combined influence of temperature, pressure and chloride on the SCC of 310S, which can be a guide to the application of 310S stainless steel in super-heater tube.

  14. Corrosion behavior of austenitic stainless steels in chloride containing ozone solutions

    SciTech Connect

    Pohjanne, P.

    1997-08-01

    Environmental concern about chlorinated organic compounds generated from traditional bleach plants has led to a development of new environmentally friendly bleaching processes. Recently, the development of ozone bleaching has progressed from pilot operations to production scale installations. Ozone is currently used as a bleaching agent of pulp as a replacement for chlorine based bleaching chemicals. Yet, there are few articles which are dealing with ozone and its effect to corrosion resistance of stainless steels or any other construction materials used in bleaching equipment. In this paper corrosion behavior of austenitic stainless steels, grades AISI 316, AISI 317LNM, UNS S31254 and UNS 32654 PM, were studied in simulated ozone bleaching environments. The laboratory tests showed that in ozone environments without chlorides the corrosion resistance of AISI 316 was superior to that of the high-alloyed stainless steels, due to the relatively low amount of alloying elements. The sequence was reversed in ozone environments containing chlorides. In the presence of chlorides AISI 316 was susceptible to localized corrosion whereas the high-alloyed UNS S31254 and UNS S 32654 PM were resistant to localized corrosion in all chloride concentrations examined.

  15. Nucleation and scattering properties of ice cloud due to seeding of sodium chloride as aqueous solution and dust

    NASA Astrophysics Data System (ADS)

    Paul, Sahana; Biswas, L. N.; De, U. K.; Goswami, K.

    Sodium chloride in three forms, as aqueous solution and as dust of two size ranges are seeded in a cold room for heterogeneous ice nucleation in the temperature range between -24 °C and 0 °C. Maximum nucleation for all the three seeding agents occurs at -21.2 °C, which is the eutectic temperature of sodium chloride and water mixture. However, the number density of ice nucleation at the eutectic temperature is highest for the finer variety of dust and lowest for the solution. On the other hand, largest size crystals are produced by the solution and smallest size crystals are produced by the finer variety of dust, at the same temperature. It is observed that the optical properties of ice cloud depends more on the crystal size. The variation of scattering co-efficient, extinction co-efficient and optical depth with temperature are noted for the scattering angles of 30°, 36°, 144° and 150°. The duration of growth of crystals and the same for the subsequent falling down of crystals can be estimated from the time variation of scattering intensity. It is observed that ice crystals due to the solution take maximum time to grow and minimum time to fall down.

  16. Application of response surface methodology (RSM) to optimize coagulation-flocculation treatment of leachate using poly-aluminum chloride (PAC) and alum.

    PubMed

    Ghafari, Shahin; Aziz, Hamidi Abdul; Isa, Mohamed Hasnain; Zinatizadeh, Ali Akbar

    2009-04-30

    Coagulation-flocculation is a relatively simple physical-chemical technique in treatment of old and stabilized leachate which has been practiced using a variety of conventional coagulants. Polymeric forms of metal coagulants which are increasingly applied in water treatment are not well documented in leachate treatment. In this research, capability of poly-aluminum chloride (PAC) in the treatment of stabilized leachate from Pulau Burung Landfill Site (PBLS), Penang, Malaysia was studied. The removal efficiencies for chemical oxygen demand (COD), turbidity, color and total suspended solid (TSS) obtained using PAC were compared with those obtained using alum as a conventional coagulant. Central composite design (CCD) and response surface method (RSM) were applied to optimize the operating variables viz. coagulant dosage and pH. Quadratic models developed for the four responses (COD, turbidity, color and TSS) studied indicated the optimum conditions to be PAC dosage of 2g/L at pH 7.5 and alum dosage of 9.5 g/L at pH 7. The experimental data and model predictions agreed well. COD, turbidity, color and TSS removal efficiencies of 43.1, 94.0, 90.7, and 92.2% for PAC, and 62.8, 88.4, 86.4, and 90.1% for alum were demonstrated. PMID:18771848

  17. Infrared optical constants of crystalline sodium chloride dihydrate: application to study the crystallization of aqueous sodium chloride solution droplets at low temperatures.

    PubMed

    Wagner, Robert; Möhler, Ottmar; Schnaiter, Martin

    2012-08-23

    Complex refractive indices of sodium chloride dihydrate, NaCl·2H(2)O, have been retrieved in the 6000-800 cm(-1) wavenumber regime from the infrared extinction spectra of crystallized aqueous NaCl solution droplets. The data set is valid in the temperature range from 235 to 216 K and was inferred from crystallization experiments with airborne particles performed in the large coolable aerosol and cloud chamber AIDA at the Karlsruhe Institute of Technology. The retrieval concept was based on the Kramers-Kronig relationship for a complex function of the optical constants n and k whose imaginary part is proportional to the optical depth of a small particle absorption spectrum in the Rayleigh approximation. The appropriate proportionality factor was inferred from a fitting algorithm applied to the extinction spectra of about 1 μm sized particles, which, apart from absorption, also featured a pronounced scattering contribution. NaCl·2H(2)O is the thermodynamically stable crystalline solid in the sodium chloride-water system below the peritectic at 273.3 K; above 273.3 K, the anhydrous NaCl is more stable. In contrast to anhydrous NaCl crystals, the dihydrate particles reveal prominent absorption signatures at mid-infrared wavelengths due to the hydration water molecules. Formation of NaCl·2H(2)O was only detected at temperatures clearly below the peritectic and was first evidenced in a crystallization experiment conducted at 235 K. We have employed the retrieved refractive indices of NaCl·2H(2)O to quantify the temperature dependent partitioning between anhydrous and dihydrate NaCl particles upon crystallization of aqueous NaCl solution droplets. It was found that the temperature range from 235 to 216 K represents the transition regime where the composition of the crystallized particle ensemble changes from almost only NaCl to almost only NaCl·2H(2)O particles. Compared to the findings on the NaCl/NaCl·2H(2)O partitioning from a recent study conducted with micron

  18. Solute-Derived Thermal Stabilization of Nano-sized Grains in Melt-Spun Aluminum

    NASA Astrophysics Data System (ADS)

    Baker, A. H.; Sanders, P. G.; Lass, E. A.; Kapoor, Deepak; Kampe, S. L.

    2016-08-01

    Thermal stabilization of nanograined metallic microstructures (or nanostructures) can be difficult due to the large driving force for growth that arises from the inherently significant boundary area. Kinetic approaches for stabilization of the nanostructure effective at low homologous temperatures often fail at higher homologous temperatures. Alternatively, thermodynamic approaches for thermal stabilization may offer higher temperature stability. In this research, modest alloying of aluminum with solute (1 pct by mole Sc, Yb, or Sr) was examined as a means to thermodynamically stabilize a bulk nanostructure at elevated temperatures. Following 1-hour annealing treatments at 673 K (400 °C) (0.72 Tm), 773 K (500 °C) (0.83 Tm), and 873 K (600 °C) (0.94 Tm), the alloys remain nanocrystalline (<100 nm) as measured by Warren-Averbach Fourier analysis of X-ray diffraction peaks and direct observation of TEM dark-field micrographs, with the efficacy of stabilization: Sr ≈ Yb > Sc. The disappearance of intermetallic phases in the Sr- and Yb-containing alloys in the X-ray diffraction spectra is observed to occur coincident with the stabilization after annealing, suggesting that precipitates dissolve and the boundaries are enriched with solute.

  19. Solute-Derived Thermal Stabilization of Nano-sized Grains in Melt-Spun Aluminum

    NASA Astrophysics Data System (ADS)

    Baker, A. H.; Sanders, P. G.; Lass, E. A.; Kapoor, Deepak; Kampe, S. L.

    2016-06-01

    Thermal stabilization of nanograined metallic microstructures (or nanostructures) can be difficult due to the large driving force for growth that arises from the inherently significant boundary area. Kinetic approaches for stabilization of the nanostructure effective at low homologous temperatures often fail at higher homologous temperatures. Alternatively, thermodynamic approaches for thermal stabilization may offer higher temperature stability. In this research, modest alloying of aluminum with solute (1 pct by mole Sc, Yb, or Sr) was examined as a means to thermodynamically stabilize a bulk nanostructure at elevated temperatures. Following 1-hour annealing treatments at 673 K (400 °C) (0.72 Tm), 773 K (500 °C) (0.83 Tm), and 873 K (600 °C) (0.94 Tm), the alloys remain nanocrystalline (<100 nm) as measured by Warren-Averbach Fourier analysis of X-ray diffraction peaks and direct observation of TEM dark-field micrographs, with the efficacy of stabilization: Sr ≈ Yb > Sc. The disappearance of intermetallic phases in the Sr- and Yb-containing alloys in the X-ray diffraction spectra is observed to occur coincident with the stabilization after annealing, suggesting that precipitates dissolve and the boundaries are enriched with solute.

  20. Removal of trivalent chromium from aqueous solution using aluminum oxide hydroxide.

    PubMed

    Bedemo, Agaje; Chandravanshi, Bhagwan Singh; Zewge, Feleke

    2016-01-01

    Water is second most essential for human being. Contamination of water makes it unsuitable for human consumption. Chromium ion is released to water bodies from various industries having high toxicity which affects the biota life in these waters. In this study aluminum oxide hydroxide was tested for its efficiency to remove trivalent chromium from aqueous solutions through batch mode experiments. Chromium concentrations in aqueous solutions and tannery waste water before and after adsorption experiments were determined using flame atomic absorption spectrometry. The effects of pH, contact time, initial concentration and adsorbent dosage on the adsorption of Cr(III) were studied. The study revealed that more than 99 % removal of Cr(III) was achieved over wide range of initial pH (3-10). The optimum conditions for the removal of Cr(III) were found to be at pH 4-6 with 40 g/L adsorbent dose at 60 min of contact time. The adsorption capacity was assessed using Langmuir and Freundlich isotherms. The equilibrium data at varying adsorbent dose obeyed the two isotherms. The adsorbent was found to be efficient for the removal of Cr(III) from tannery waste effluent. PMID:27547663

  1. Effect of Polyvnylpyrrolidone (PVP) in Binary Solution on the Performance of Polyethersulfone Hollow Fibre Membrane for Sodium Chloride Separation

    NASA Astrophysics Data System (ADS)

    Bolong, N.; Ismail, A. F.; Salim, M. R.

    2010-03-01

    In membrane preparation, phase inversion is a versatile technique that allow polymer to be transformed from liquid to a solid state in a controlled manner. The preparation and process involves many factors and parameters specifically in fabricating hollow fibre membrane. In this study, dope solution factor in the process of fabricating hollow fibre membrane were explored. The effects of polymer concentration and polyvinylpyrrolidone (PVP) as additive in the dope solution on the morphology and separation performance were found able to produced high porous membranes, well interconnected pores and surface properties. Employing polyethersulfone (PES) as polymer, hollow fibre membranes were fabricated using N-methyl-2-pyrrolidone (NMP) as solvent and using water as the external coagulant. Finally the fabricated ultrafiltration membranes were characterized and evaluated based on solute transport concentration (sodium chloride) and pure water permeation properties.

  2. Development of a combined solution formulation of atropine sulfate and obidoxime chloride for autoinjector and evaluation of its stability.

    PubMed

    Ettehadi, Hossein Ali; Ghalandari, Rouhollah; Shafaati, Alireza; Foroutan, Seyed Mohsen

    2013-01-01

    Atropine (AT) and oximes, alone or in combination, have been proven greatly valuable therapeutics in the treatment of organophosphates intoxications. An injectable mixture of AT and obidoxime (OB) was formulated for the administration by automatic self-injector. The aqueous single dose solution contained 275 mg obidoxime chloride and 2.5 mg atropine sulfate per 1 mL (220 mg and 2 mg per 0.8 effective dose, respectively). The final solution was sterilized by filtration through a 0.22 μm pore size filter. This more concentrated solution allowed to use a smaller size and lighter weight cartridge. Quality control tests, including assay of the two major compounds were performed separately, using reversed-phase HPLC methods. Besides, the stability test was carried out according to ICH guideline for the accelerated test. The obtained results showed that the proposed formulation is stable over a period of 2 years after preparation. PMID:24250669

  3. Development of a Combined Solution Formulation of Atropine Sulfate and Obidoxime Chloride for Autoinjector and Evaluation of Its Stability

    PubMed Central

    Ettehadi, Hossein Ali; Ghalandari, Rouhollah; Shafaati, Alireza; Foroutan, Seyed Mohsen

    2013-01-01

    Atropine (AT) and oximes, alone or in combination, have been proven greatly valuable therapeutics in the treatment of organophosphates intoxications. An injectable mixture of AT and obidoxime (OB) was formulated for the administration by automatic self-injector. The aqueous single dose solution contained 275 mg obidoxime chloride and 2.5 mg atropine sulfate per 1 mL (220 mg and 2 mg per 0.8 effective dose, respectively). The final solution was sterilized by filtration through a 0.22 μm pore size filter. This more concentrated solution allowed to use a smaller size and lighter weight cartridge. Quality control tests, including assay of the two major compounds were performed separately, using reversed-phase HPLC methods. Besides, the stability test was carried out according to ICH guideline for the accelerated test. The obtained results showed that the proposed formulation is stable over a period of 2 years after preparation. PMID:24250669

  4. Electrochemical process combined with UV light irradiation for synergistic degradation of ammonia in chloride-containing solutions.

    PubMed

    Xiao, Shuhu; Qu, Jiuhui; Zhao, Xu; Liu, Hujuan; Wan, Dongjin

    2009-03-01

    An electrochemical process combined with ultraviolet light irradiation (UPE) using nonphotoactive dimensionally stable anodes (DSAs) like RuO2/Ti and IrO2/Ti in the presence of chlorides was investigated for ammonia degradation. In this process, the in situ electrogenerated active chlorine and in situ photogenerated chlorine radicals were responsible for the high efficiency of ammonia degradation. More than 97% of ammonia was converted to nitrogen and a significantly synergistic effect was confirmed. Compared with the single electrochemical (E) and photochemical (P) process, the degradation rates of ammonia and the average current efficiencies (ACEs) of the UPE process increased by 1.5 and 1.7 times using RuO2/Ti and IrO2/Ti electrodes, respectively. On the basis of the linear voltammograms, Electrochemical Impedance Spectra (EIS), UV-vis spectra, Electron Spin Resonance (ESR) analysis and a series of experiments designed, the synergistic mechanism was investigated. In addition, this unique process succeeded in transferring the reaction from the electrode surface to the bulk of the solution compared with the conventional photoelectrocatalytic (PEC) process. The loss of chloride decreased from 21.0% to 7.2% and the recycle of chloride was accelerated in the UPE process. Finally the effects of initial pH, current density and ammonia-nitrogen concentration were discussed. Results indicated that pH and ammonia concentration exerted little influences on the degradation rates and current density was the "rate-determining" factor. PMID:19135227

  5. n-Propylpyridinium chloride-modified poly(dimethylsiloxane) elastomeric networks: preparation, characterization, and study of metal chloride adsorption from ethanol solutions.

    PubMed

    Pissetti, Fábio L; Magosso, Herica A; Yoshida, Inez V P; Gushikem, Yoshitaka; Myernyi, Sergiy O; Kholin, Yuriy V

    2007-10-01

    An n-propylpyridinium chloride-modified PDMS elastomeric network, PDMS/Py(+)Cl(-), was prepared from linear PDMS chains containing Si(CH(3))(2)OH end-groups cross-linked by 3-chloropropyltrimethoxysilane and posterior reaction with pyridine. PDMS/Py(+)Cl(-) material was structurally characterized by infrared spectroscopy (IR) and solid state (13)C and (29)Si NMR. Thermogravimetric analysis of the product showed good thermal stability, with the initial temperature of weight loss at 450 K. The ion-exchange capacity of the PDMS/Py(+)Cl(-) was 0.65 mmol g(-1). Metal halides, MCl(z) [M=Fe(3+), Cu(2+), and Co(2+)], were adsorbed by the modified solid from ethanol solutions as neutral species by forming the surface anionic complexes MCl(z+n)(n-). The nature of the anionic complex structure was proposed by UV-vis diffuse reflectance spectra. The species adsorbed were FeCl(-)(4), CuCl(2-)(4), and CoCl(2-)(4). The specific sorption capacities and the heterogeneous stability constants of the immobilized metal complexes were determined with the aid of computational procedures. The trend in affinities of PDMS/Py(+)Cl(-) for the metal halides were found to be FeCl(3)>CuCl(2) approximately CoCl(2). PMID:17582428

  6. Effect of divalent ions on electroosmotic transport in a sodium chloride aqueous solution confined in an amorphous silica nanochannel

    NASA Astrophysics Data System (ADS)

    Conlisk, A. T.; Zambrano, Harvey; Cevheri, Necmettin; Yoda, Minami; Computational Micro-; Nanofluidics Lab Team; The Fluids, Optical; Interfacial Diagnostics Lab Team

    2012-11-01

    A critical enabling technology for the next generation of nanoscale devices, such as nanoscale ``lab on a chip'' systems, is controlling electroosmotic flow (EOF) in nanochannels. In this work, we control EOF in an aqueous sodium chloride (NaCl) solution confined in a silica nanochannel by systematically adding different amounts of divalent ions. Multivalent ions have a different affinity for the silica surface and different hydration characteristics in comparison to monovalent ions. Therefore by adding Mg++ and Ca++ to the sodium chloride solution, the electroosmotic velocity and the structure of the electrical double layer will be modified. The effects of adding Mg++ and Ca++ will be compared using non-equilibrium molecular dynamics simulations of the EOF at different electric fields of a NaCl solution in a silica nanochannel with different fractions of Ca++ and Mg++ ions. In general, the wall zeta-potential magnitude, and hence the EOF velocity, decreases as the Ca++ or Mg++ concentration increases. The system responds linearly with electric field. We will compare the computational results with the experimental data of Cevheri and Yoda (2012). This work is supported by Army Research Office (ARO) grant number W911NF1010290.

  7. Comparison of Electrochemical Methods to Determine Crevice Corrosion Repassivation Potential of Alloy 22 in Chloride Solutions

    SciTech Connect

    K. Evans; A. Yilmaz; S. Day; L. Wong; J. Estill

    2004-08-23

    Alloy 22 (N06022) is a nickel-based alloy highly resistant to corrosion. In some aggressive conditions of high chloride concentration, temperature and applied potential, Alloy 22 may suffer crevice corrosion, a form of localized corrosion. There are several electrochemical methods that can be used to determine localized corrosion in metallic alloys. One of the most popular for rapid screening is the cyclic potentiodynamic polarization (CPP). This work compares the repassivation potentials obtained using CPP to related repassivation potential values obtained using the Tsujikawa-Hisamatsu Electrochemical (THE) method and the potentiostatic (POT) method. Studied variables included temperature and chloride concentration. The temperature was varied from 30 C and 120 C and the chloride concentration was varied between 0.0005 M to 4 M. Results show that similar repassivation potentials were obtained for Alloy 22 using CPP and THE methods. Generally, under more aggressive conditions, the repassivation potentials were more conservative using the CPP method. POT tests confirmed the validity of the repassivation potential as a threshold below which localized corrosion does not nucleate. The mode of attack in the tested specimens varied depending if the test method was CPP or THE; however, the repassivation potential remained the same.

  8. Shock Hugoniot and equations of states of water, castor oil, and aqueous solutions of sodium chloride, sucrose and gelatin

    NASA Astrophysics Data System (ADS)

    Gojani, A. B.; Ohtani, K.; Takayama, K.; Hosseini, S. H. R.

    2016-01-01

    This paper reports a result of experiments for the determination of reliable shock Hugoniot curves of liquids, in particular, at relatively low pressure region, which are needed to perform precise numerical simulations of shock wave/tissue interaction prior to the development of shock wave related therapeutic devices. Underwater shock waves were generated by explosions of laser ignited 10 mg silver azide pellets, which were temporally and spatially well controlled. Measuring temporal variation of shock velocities and over-pressures in caster oil, aqueous solutions of sodium chloride, sucrose and gelatin with various concentrations, we succeeded to determine shock Hugoniot curves of these liquids and hence parameters describing Tait type equations of state.

  9. Effect of pore water velocities and solute input methods on chloride transport in the undisturbed soil columns of Loess Plateau

    NASA Astrophysics Data System (ADS)

    Zhou, BeiBei; Wang, QuanJiu

    2016-04-01

    Studies on solute transport under different pore water velocity and solute input methods in undisturbed soil could play instructive roles for crop production. Based on the experiments in the laboratory, the effect of solute input methods with small pulse input and large pulse input, as well as four pore water velocities, on chloride transport in the undisturbed soil columns obtained from the Loess Plateau under controlled condition was studied. Chloride breakthrough curves (BTCs) were generated using the miscible displacement method under water-saturated, steady flow conditions. Using the 0.15 mol L-1 CaCl2 solution as a tracer, a small pulse (0.1 pore volumes) was first induced, and then, after all the solution was wash off, a large pulse (0.5 pore volumes) was conducted. The convection-dispersion equation (CDE) and the two-region model (T-R) were used to describe the BTCs, and their prediction accuracies and fitted parameters were compared as well. All the BTCs obtained for the different input methods and the four pore water velocities were all smooth. However, the shapes of the BTCs varied greatly; small pulse inputs resulted in more rapid attainment of peak values that appeared earlier with increases in pore water velocity, whereas large pulse inputs resulted in an opposite trend. Both models could fit the experimental data well, but the prediction accuracy of the T-R was better. The values of the dispersivity, λ, calculated from the dispersion coefficient obtained from the CDE were about one order of magnitude larger than those calculated from the dispersion coefficient given by the T-R, but the calculated Peclet number, Pe, was lower. The mobile-immobile partition coefficient, β, decreased, while the mass exchange coefficient increased with increases in pore water velocity.

  10. Effects of liquid aluminum chloride additions to poultry litter on broiler performance, ammonia emissions, soluble phosphorus, total volatile Fatty acids, and nitrogen contents of litter.

    PubMed

    Choi, I H; Moore, P A

    2008-10-01

    Recent studies have shown that the use of aluminum sulfate [alum, Al2(SO4)3.14H2O] and aluminum chloride (AlCl3) additions to animal manures are more effective than other chemicals in reducing ammonia (NH3) emissions and P solubility. Although the use of Al2(SO4)3.14H2O has been intensively used in the poultry industry for many years, no research has been conducted to evaluate the effect of liquid AlCl3 on these parameters. The objectives of this study were to determine the effects of applying liquid AlCl3 to poultry litter on 1) broiler performance, 2) NH3 fluxes, and 3) litter chemical characteristics, including soluble reactive P, total volatile fatty acids, and N content. Eight hundred broiler chicks were placed into 16 floor pens (50 birds/pen) in a single house for 6 wk. Liquid AlCl3 treatments were sprayed on the litter surface at rates of 100, 200, and 300 g of liquid AlCl3/kg of litter; un-treated litter served as controls. At the 2 lower rates, liquid AlCl3 treatments tended to improve weight gain and feed intake but had no effect on feed conversion or mortality, whereas the higher rate (300 g/kg of litter) had a negative effect on intake. Application of 100, 200, and 300 g of liquid AlCl3 reduced NH3 fluxes by 63, 76, and 76% during the 6-wk period, respectively, compared with the controls. Liquid AlCl3 additions reduced litter soluble reactive P contents by 24, 30, and 36%, respectively, at the low, medium, and high rates. Total volatile fatty acid contents (odor precursors) in litter were reduced by 20, 50, and 51%, respectively, with 100, 200, and 300 g of liquid AlCl3/kg of litter. Liquid AlCl3 additions increased total N, inorganic N, and plant available N contents in litter. These results indicate that liquid AlCl3 additions at the lower rates can provide significant positive environmental benefits to broiler operations. PMID:18809856

  11. Selective conversion of cellulose in corncob residue to levulinic acid in an aluminum trichloride-sodium chloride system.

    PubMed

    Li, Jianmei; Jiang, Zhicheng; Hu, Libin; Hu, Changwei

    2014-09-01

    Increased energy consumption and environmental concerns have driven efforts to produce chemicals from renewable biomass with high selectivity. Here, the selective conversion of cellulose in corncob residue, a process waste from the production of xylose, to levulinic acid was carried out using AlCl3 as catalyst and NaCl as promoter by a hydrothermal method at relatively low temperature. A levulinic acid yield of 46.8 mol% was obtained, and the total selectivity to levulinic acid with formic acid was beyond 90%. NaCl selectively promoted the dissolution of cellulose from corncob residue, and significantly improved the yield and selectivity to levulinic acid by inhibiting lactic acid formation in the subsequent dehydration process. Owing to the salt effect of NaCl, the obtained levulinic acid could be efficiently extracted to tetrahydrofuran from aqueous solution. The aqueous solution with AlCl3 and NaCl could be recycled 4 times. Because of the limited conversion of lignin, this process allows for the production of levulinic acid with high selectivity directly from corncob residue in a simple separation process. PMID:25045141

  12. High efficient removal of fluoride from aqueous solution by a novel hydroxyl aluminum oxalate adsorbent.

    PubMed

    Wu, Shibiao; Zhang, Kaisheng; He, Junyong; Cai, Xingguo; Chen, Kai; Li, Yulian; Sun, Bai; Kong, Lingtao; Liu, Jinhuai

    2016-02-15

    A novel adsorbent, hydroxyl aluminum oxalate (HAO), for the high efficient removal of fluoride from aqueous solution was successfully synthesized. The adsorbent was characterized and its performance in fluoride (F(-)) removal was evaluated for the first time. Kinetic data reveal that the F(-) adsorption is rapid in the beginning followed by a slower adsorption process; 75.9% adsorption can be achieved within 1min and only 16% additional removal occurred in the following 239min. The F(-) adsorption kinetics was well described by the pseudo second-order kinetic model. The calculated adsorption capacity of this adsorbent for F(-) by Langmuir model was 400mgg(-1) at pH 6.5, which is one of the highest capabilities of today's materials. The thermodynamic parameters calculated from the temperature-dependent isotherms indicate that the adsorption reaction of F(-) on the HAO is a spontaneous process. The FT-IR spectra of HAO before and after adsorbing F(-) show adsorption mechanism should be hydroxyl and oxalate interchange with F(-). PMID:26624529

  13. The role of macrocyclic compounds in the extraction and possible separation of platinum and rhodium from chloride solutions.

    PubMed

    Jyothi, Rajesh Kumar; Lee, Jin-Young

    2016-01-01

    Macrocyclic compounds (crown ethers), specifically 18-crown-6 (18-C-6), benzo-15-crown-5 (B-15-C-5), di-benzo-18-crown-6 (DB-18-C-6) and di-cyclohexano-18-crown-6 (DC-18C-6), are used as extractants as well as synergists with amine-group extractants. Platinum and rhodium belong to platinum-group metals (PGMs) and have very similar ionic radii and similar properties. The separation of PGMs is most useful for the preparation of functional materials. Macrocyclic compounds are tested for platinum and rhodium separation and are found to achieve marginal separation. Amines (used as extractants) are paired with macrocyclic compounds (used as synergists), and the separation factor between platinum and rhodium is increased with synergistic enhancement from a chloride solution. The present study discusses extraction chemistry, separation factors and the synergy between platinum and rhodium from chloride solutions. To ensure accurate data, the aqueous samples in this study are analyzed using an inductively coupled plasma optical emission spectrometer (ICP-OES). PMID:27283394

  14. The role of macrocyclic compounds in the extraction and possible separation of platinum and rhodium from chloride solutions

    PubMed Central

    Jyothi, Rajesh Kumar; Lee, Jin-Young

    2016-01-01

    Macrocyclic compounds (crown ethers), specifically 18-crown-6 (18-C-6), benzo-15-crown-5 (B-15-C-5), di-benzo-18-crown-6 (DB-18-C-6) and di-cyclohexano-18-crown-6 (DC-18C-6), are used as extractants as well as synergists with amine-group extractants. Platinum and rhodium belong to platinum-group metals (PGMs) and have very similar ionic radii and similar properties. The separation of PGMs is most useful for the preparation of functional materials. Macrocyclic compounds are tested for platinum and rhodium separation and are found to achieve marginal separation. Amines (used as extractants) are paired with macrocyclic compounds (used as synergists), and the separation factor between platinum and rhodium is increased with synergistic enhancement from a chloride solution. The present study discusses extraction chemistry, separation factors and the synergy between platinum and rhodium from chloride solutions. To ensure accurate data, the aqueous samples in this study are analyzed using an inductively coupled plasma optical emission spectrometer (ICP-OES). PMID:27283394

  15. Cation effects on interfacial water organization of aqueous chloride solutions. I. Monovalent cations: Li+, Na+, K+, and NH4(+).

    PubMed

    Hua, Wei; Verreault, Dominique; Huang, Zishuai; Adams, Ellen M; Allen, Heather C

    2014-07-17

    The influence of monovalent cations on the interfacial water organization of alkali (LiCl, NaCl, and KCl) and ammonium chloride (NH4Cl) salt solutions was investigated using surface-sensitive conventional vibrational sum frequency generation (VSFG) and heterodyne-detected (HD-)VSFG spectroscopy. It was found in the conventional VSFG spectra that LiCl and NH4Cl significantly perturb water’s hydrogen-bonding network. In contrast, NaCl and KCl had little effect on the interfacial water structure and exhibited weak concentration dependency. The Im χs(2)(ωIR) spectra from HD-VSFG further revealed that, for all chloride solutions, the net transition dipole moments of hydrogen-bonded water molecules (O → H) are oriented more toward the vapor phase relative to neat water. This suggests the presence of an interfacial electric field generated from the formation of an ionic double layer in the interfacial region with a distribution of Cl(-) ions located above the countercations, in agreement with predictions from MD simulations. The magnitude of this electric field shows a small but definite cation specificity and follows the order Li(+) ≈ Na(+) > NH4(+) > K(+). The observed trend was found to be in good agreement with previously published surface potential data. PMID:24798506

  16. The role of macrocyclic compounds in the extraction and possible separation of platinum and rhodium from chloride solutions

    NASA Astrophysics Data System (ADS)

    Jyothi, Rajesh Kumar; Lee, Jin-Young

    2016-06-01

    Macrocyclic compounds (crown ethers), specifically 18-crown-6 (18-C-6), benzo-15-crown-5 (B-15-C-5), di-benzo-18-crown-6 (DB-18-C-6) and di-cyclohexano-18-crown-6 (DC-18C-6), are used as extractants as well as synergists with amine-group extractants. Platinum and rhodium belong to platinum-group metals (PGMs) and have very similar ionic radii and similar properties. The separation of PGMs is most useful for the preparation of functional materials. Macrocyclic compounds are tested for platinum and rhodium separation and are found to achieve marginal separation. Amines (used as extractants) are paired with macrocyclic compounds (used as synergists), and the separation factor between platinum and rhodium is increased with synergistic enhancement from a chloride solution. The present study discusses extraction chemistry, separation factors and the synergy between platinum and rhodium from chloride solutions. To ensure accurate data, the aqueous samples in this study are analyzed using an inductively coupled plasma optical emission spectrometer (ICP-OES).

  17. Ion-exchange extraction of platinum(II,IV) from chloride solutions in the presence of iron(III)

    NASA Astrophysics Data System (ADS)

    Kononova, O. N.; Duba, E. V.; Karplyakova, N. S.; Krylov, A. S.

    2015-08-01

    The sorption concentration of platinum(II,IV) in the presence of iron(III) is studied on new samples of domestically produced ionites of the CYBBER brand. In comparing the sorption and kinetic properties of the new ionites to those of sorbents of the Purolite brand studied earlier, the higher effectiveness of the former is demonstrated via the extraction of platinum(II,IV) ions from strongly and weakly acidic chloride solutions. It is found that the sorbed platinum ions can be completely separated from iron(III) ions through separate elution using 0.01-0.001 M HCl (iron ions) and a thiourea solution (80 g/L) in 0.3 M H2SO4 (platinum ions).

  18. Photodynamic therapy disinfection of carious tissue mediated by aluminum-chloride-phthalocyanine entrapped in cationic liposomes: an in vitro and clinical study.

    PubMed

    Longo, João Paulo F; Leal, Soraya C; Simioni, Andreza R; de Fátima Menezes Almeida-Santos, Maria; Tedesco, Antônio C; Azevedo, Ricardo B

    2012-05-01

    Photodynamic therapy (PDT) is a technique employed in the treatment of several superficial infections, such as caries. PDT uses a non-toxic drug termed photosensitizer (PS) followed by light irradiation. The cytotoxic effects of the therapy are related to the production of reactive species produced after light activation of a photosensitizer, which reacts with surrounding molecules and disrupts several of the cell's functions. Within this context, this study aimed to develop a clinical protocol involving PDT application mediated by aluminum-chloride-phthalocyanine (AlClPc) entrapped in cationic liposomes against cariogenic bacteria in caries lesions. Cationic liposomes were used to delivery AlClPc preferentially to bacterial cells due to the strong anionic superficial charges of these cell types. The results are represented in two fundamental steps: (1) in vitro evaluation of AlClPc delivery to cariogenic bacteria and pulp cells, as well as its potential phototoxicity; (2) a clinical study involving volunteer patients that were treated with the PDT protocol mediated by AlClPc-cationic liposome. The main results showed that the AlClPc-cationic liposome was preferentially absorbed by bacterial cells compared to eukaryotic dental pulp cells, and it was efficient in the reduction of microbial load from bacterial cultures. In addition, the clinical study showed a mean reduction of 82% of total bacterial in the treated cavities after PDT application. Taken together, the results presented in this study showed that the antimicrobial PDT protocol mediated by cationic liposomes containing AlClPc is safety for clinical application and is efficient in the reduction of bacterial load in caries lesions. PMID:21809069

  19. Slow strain rate fracture of high-strength steel at controlled electrochemical potentials in ammonium chloride, potassium chloride, and ammonium nitrate solutions

    SciTech Connect

    Nguyen, D.T.; Nichols, D.E. ); Daniels, R.D. . School of Chemical Engineering and Materials Science)

    1992-08-15

    Slow strain rate testing has been undertaken to determine the effects of individual chemical species on the fracture process of high-strength 4340 steel. Test environments included potassium chloride, ammonium nitrate, and ammonium chloride at concentrations from 0.001 to 1.0 mole por liter at ambient temperature. Tests were performed at cathodic and anodic controlled potentials, as well as at the open-circuit potential, to delineate the stress corrosion cracking range.

  20. A Fiber-Optic Sensor Using an Aqueous Solution of Sodium Chloride to Measure Temperature and Water Level Simultaneously

    PubMed Central

    Yoo, Wook Jae; Sim, Hyeok In; Shin, Sang Hun; Jang, Kyoung Won; Cho, Seunghyun; Moon, Joo Hyun; Lee, Bongsoo

    2014-01-01

    A fiber-optic sensor system using a multiplexed array of sensing probes based on an aqueous solution of sodium chloride (NaCl solution) and an optical time-domain reflectometer (OTDR) for simultaneous measurement of temperature and water level is proposed. By changing the temperature, the refractive index of the NaCl solution is varied and Fresnel reflection arising at the interface between the distal end of optical fiber and the NaCl solution is then also changed. We measured the modified optical power of the light reflected from the sensing probe using a portable OTDR device and also obtained the relationship between the temperature of water and the optical power. In this study, the water level was simply determined by measuring the signal difference of the optical power due to the temperature difference of individual sensing probes placed inside and outside of the water. In conclusion, we demonstrate that the temperature and water level can be obtained simultaneously by measuring optical powers of light reflected from sensing probes based on the NaCl solution. It is anticipated that the proposed fiber-optic sensor system makes it possible to remotely monitor the real-time change of temperature and water level of the spent fuel pool during a loss of power accident. PMID:25310471

  1. Growth mechanisms of iron oxide particles of differing morphologies from the forced hydrolysis of ferric chloride solutions

    SciTech Connect

    Bailey, J.K.; Brinker, C.J. ); MeCartney, M.L. )

    1993-04-01

    To determine the growth mechanisms responsible for the different morphologies, the authors used time resolved transmission electron microscopy to follow the growth of iron oxide particles produced by the forced hydrolysis of ferric chloride solutions. The growth of three different hematite particle morphologies were investigated: cubes, spheres, and so-called double ellipsoids. The morphology of the particles depends on the concentration of FeCl[sub 3], the pH, and the temperature of aging. All solutions were seen to first produce rod-like particles of akaganeite ([beta]-FeOOH) which would then transform to hematite ([alpha]-Fe[sub 2]O[sub 3]), leading under different conditions to spheres, cubes, or double ellipsoids. For all solutions, the initially produced akaganeite rods form by homogeneous nucleation and subsequent growth. The hematite particles are produced by dissolution of the akaganeite rods and reprecipitation as hematite. For the double-ellipsoid-producing solution, the akaganeite rods remain unaggregated in solution. Hematite heterogeneously nucleates on these rods. In addition to growing outward, the hematite particle uses the rod as a template, and a collar forms, which grows along the rod, producing the double-ellipsoid shape. For a sphere-producing solution, the [beta]-FeOOH rods also remain unaggregated in solution but the akaganeite rods which are formed are shorter and dissolve before the growing hematite particles can use the rods as templates. For the cube-producing solution, the initially produced akaganeite rods aggregate into rafts. These rafts, formed from rods of similar length, have a cubic shape that they impart to the hematite which nucleates on the akaganeite raft. The findings indicate that the concentrations of starting compounds not only influence the kinetics of the reaction, but also influence the colloidal behavior.

  2. Effect of SO4 2-/Al3+ ratio and OH-/Al3+ value on the characterization of coagulant poly-aluminum-chloride-sulfate (PACS) and its coagulation performance in water treatment.

    PubMed

    Gao, Baoyu; Yue, Qinyan

    2005-10-01

    A poly-aluminum-chloride-sulfate (PACS) was prepared at various experimental conditions. It was found that the coagulation performance of PACS in water treatment was affected by the PACS particle size distribution and zeta potential value. The experimental results indicated that the PACS particle size distribution and zeta potential value were highly influenced by SO(4)(2-)/Al(3+) molar ratio and bacicities (gamma,gamma=[OH]/[Al]) value. At a fixed gamma value of 2.0, the average PACS particle size increased from 25 to 80nm with the increase of SO(4)(2-)/Al(3+) ratio from 0 to 0.1. Further increase of the SO(4)(2-)/Al(3+) ratio resulted in acute increment particle size of PACS extremely, which can be attributed to its aggregation. At a fixed SO(4)(2-)/Al(3+) ratio of 0.0664, the largest average size of PACS occurred at gamma=2.0. It was also found that the zeta potential value of PACS was strongly influenced by the SO(4)(2-)/Al(3+) ratio, gamma value and pH of the aquatic solution. The zeta potential value of PACS increased with increasing of SO(4)(2-)/Al(3+) ratio. At a fixed SO(4)(2-)/Al(3+) ratio of 0.0664, PACS achieved greatest zeta potential value at gamma value of around 2.0. The maximum positive zeta potential value of PACS was found at pH5.3. At a fixed gamma value of 2.0 and SO(4)(2-)/Al(3+) ratio of 0.0664, the PACS achieved an optimum natural organic matter and turbidity removal efficiency. PMID:16202812

  3. Lead, cadmium and aluminum in Canadian infant formulae, oral electrolytes and glucose solutions

    PubMed Central

    Dabeka, Robert; Fouquet, Andre; Belisle, Stephane; Turcotte, Stephane

    2011-01-01

    Lead (Pb), cadmium (Cd) and aluminum (Al) were determined in 437 individual samples of infant formulae, oral electrolytes and 5% glucose solutions available in Canada. In the electrolytes, Cd and Pb concentrations were all below 0.01 and 0.041 ng g−1, respectively. In the 5% glucose solutions, Pb and Cd levels averaged 0.01 and 0.09 ng g−1, respectively. Reported on an as-consumed basis, Pb levels in milk- and soya-based formulae averaged 0.90 and 1.45 ng g−1, respectively, while Cd levels averaged 0.23 and 1.18 ng g−1, respectively Average Al levels on an as-consumed basis were 440 ng g−1 (range 10–3400 ng g−1) in milk-based formulae and 730 ng g−1 (range 230–1100 ng g−1) in soy-based formulae. Al concentrations increased in the following order: plain formula < low-iron formula < iron-supplemented formula < casein hydrolysate formula ≈ premature formula ≤ soy formula. For example, in the powdered formulae, average Al concentrations were 18 ng g−1 for plain milk-based, 37 ng g−1 for low-iron, 128 ng g−1 for iron supplemented, 462 ng g−1 for lactose-free, 518 ng g−1 for hypoallergenic and 619 ng g−1 for soy-based formula. Al concentrations, as-consumed, increased with decreasing levels of concentration: powder < concentrated liquid < ready-to-use. Formulae stored in glass bottles contained between 100 and 300 ng g−1 more Al than the same formulae stored in cans. The source of the increased Al did not appear to be the glass itself, because most electrolytes and glucose solutions, also stored in glass, contained less than 8 ng g−1 Al. Corresponding differences in Pb and Cd levels were not observed. Al concentrations varied substantially among manufacturers; however, all manufacturers were able to produce plain milk-based formulae containing less than 50 ng g−1 Al, i.e. within the range of Al concentrations found in human milk. Next to soya-based and hypoallergenic formulae, premature formulae contained among the highest

  4. Effects of solution conditions and surface chemistry on the adsorption of three recombinant botulinum neurotoxin antigens to aluminum salt adjuvants.

    PubMed

    Vessely, Christina; Estey, Tia; Randolph, Theodore W; Henderson, Ian; Nayar, Rajiv; Carpenter, John F

    2007-09-01

    Botulinum neurotoxin (BoNT) is a biological warfare threat. Protein antigens have been developed against the seven major BoNT serotypes for the development of a recombinant protein vaccine. This study is an evaluation of adsorption profiles for three of the recombinant protein antigens to aluminum salt adjuvants in the development of a trivalent vaccine against BoNT. Adsorption profiles were obtained over a range of protein concentrations. The results document that charge-charge interactions dominate the adsorption of antigen to adjuvant. Optimal conditions for adsorption were determined. However, potency studies and solution stability studies indicated the necessity of using aluminum hydroxide adjuvant at low pH. To improve the adsorption profiles to AlOH adjuvant, phosphate ions were introduced into the adsorption buffers. The resulting change in the adjuvant chemistry led to an improvement of adsorption of the BoNT antigens to aluminum hydroxide adjuvant while maintaining potency. Competitive adsorption profiles were also determined, and showed changes in maximum adsorption from mixed solutions compared to adsorption from individual protein solutions. The adsorption profiles for each protein varied due to differences in adsorption mechanism and affinity for the adjuvant surface. These results emphasize the importance of evaluating competitive adsorption in the development of multivalent vaccine products. PMID:17518359

  5. Recovery of gallium from aluminum industry residues

    SciTech Connect

    Carvalho, M.S.; Neto, K.C.M.; Nobrega, A.W.; Medeiros, J.A.

    2000-01-01

    A procedure is proposed to recover gallium from flue dust aluminum residues produced in plants by using solid-phase extraction with a commercial polyether-type polyurethane foam (PUF). Gallium can be separated from high concentrations of aluminum, iron, nickel, titanium, vanadium, copper, zinc, sulfate, fluoride, and chloride by extraction with PUF from 3 M sulfuric acid and 3 M sodium chloride concentration medium with at least a 92% efficiency. Gallium backextraction was fast and quantitative with ethanol solution. In all recovery steps commercial-grade reagents could be used, including tap water. The recovered gallium was precipitated with sodium hydroxide solution, purified by dissolution and precipitation, calcinated, and the final oxide was 98.6% pure.

  6. Assessing the effectiveness of 30% sodium chloride aqueous solution for the preservation of fixed anatomical specimens: a 5-year follow-up study

    PubMed Central

    de Oliveira, Fabrício Singaretti

    2014-01-01

    Anatomical specimens used in human or veterinary anatomy laboratories are usually prepared with formaldehyde (a cancerous and teratogenic substance), glycerin (an expensive and viscous fluid), or ethanol (which is flammable). This research aimed to verify the viability of an aqueous 30% sodium chloride solution for preservation of anatomical specimens previously fixed with formaldehyde. Anatomical specimens of ruminant, carnivorous, equine, swine and birds were used. All were previously fixed with an aqueous 20% formaldehyde solution and held for 7 days in a 10% aqueous solution of the same active ingredient. During the first phase of the experiment, small specimens of animal tissue previously fixed in formaldehyde were distributed in vials with different concentrations of formaldehyde, with or without 30% sodium chloride solution, a group containing only 30% sodium chloride, and a control group containing only water. During this phase, no contamination was observed in any specimen containing 30% sodium chloride solution, whether alone or in combination with different concentrations of formaldehyde. In the second phase of the experiment, the 30% sodium chloride solution, found to be optimal in the first phase of the experiment, was tested for its long-term preservation properties. For a period of 5 years, the preserved specimens were evaluated three times a week for visual contamination, odors, and changes in color and texture. There was no visual contamination or decay found in any specimen. Furthermore, no strange odors, or changes in color or softness were noted. The 30% sodium chloride solution was determined to be effective in the preservation of anatomic specimens previously fixed in formaldehyde. PMID:24762210

  7. Viscosities of the ternary solution dimethyl sulfoxide/water/sodium chloride at subzero temperatures and their application in cryopreservation.

    PubMed

    Zhang, Shaozhi; Yu, Xiaoyi; Chen, Zhaojie; Chen, Guangming

    2013-04-01

    Vitrification is considered as the most promising method for long-term storage of tissues and organs. An effective way to reduce the accompanied cryoprotectant (CPA) toxicity, during CPA addition/removal, is to operate at low temperatures. The permeation process of CPA into/out of biomaterials is affected by the viscosity of CPA solution, especially at low temperatures. The objective of the present study is to measure the viscosity of the ternary solution, dimethyl sulfoxide (Me2SO)/water/sodium chloride (NaCl), at low temperatures and in a wide range of concentrations. A rotary viscometer coupled with a low temperature thermostat bath was used. The measurement was carried out at temperatures from -10 to -50°C. The highest mass fraction of Me2SO was 75% (w/w) and the lowest mass fraction of Me2SO was the value that kept the solution unfrozen at the measurement temperature. The concentration of NaCl was kept as a constant [0.85% (w/w), the normal salt content of extracellular fluids]. The Williams-Landel-Ferry (WLF) model was employed to fit the obtained viscosity data. As an example, the effect of solution viscosity on modeling the permeation of Me2SO into articular cartilage was qualitatively analyzed. PMID:23376371

  8. In situ X-ray microprobe study of salt layers during anodic dissolution of stainless steel in chloride solution

    SciTech Connect

    Isaacs, H.S.; Cho, J.H.; Rivers, M.L.; Sutton, S.R.

    1995-04-01

    Salt layers play an important role in many electrochemical dissolution processes. The composition of salt films formed on austenitic stainless steel have, for the first time, been determined using in situ energy dispersive X-ray fluorescence microanalysis during dissolution in a chloride solution. The electrode was the cross section of a nickel/chromium steel foil sandwiched between plastic sheets. The foil was electrochemically dissolved producing a pit 1.6 mm deep. The electrode configuration simulated localized corrosion with a one-dimensional diffusion geometry. X-ray fluorescence intensities of chromium K{sub {alpha}}, iron K{sub {alpha}}, an nickel K{sub {beta}} energies were measured as the steel/solution interface traversed a 6 {mu}m, polychromatic, high-intensity X-ray beam. Qualitative determinations were made of the composition of the salt layer and the composition of the saturated solution. Salt layer thickness was found to increase with increased applied potentials. The salt layer was found to be rich in iron and depleted in nickel and, particularly, chromium. The effective diffusion coefficients of the dissolved species were determined from the composition of the saturated solution at the interface. Nickel showed the highest and chromium the lowest effective diffusion coefficient.

  9. Virus inactivation in aluminum and polyaluminum coagulation.

    PubMed

    Matsui, Yoshihiko; Matsushita, Taku; Sakuma, Satoru; Gojo, Takahito; Mamiya, Teppei; Suzuoki, Hiroshi; Inoue, Takanobu

    2003-11-15

    Inorganic aluminum salts, such as aluminum sulfate, are coagulants that cause small particles, such as bacteria and viruses as well as inorganic particles, to destabilize and combine into larger aggregates. In this investigation, batch coagulation treatments of water samples spiked with Qbeta, MS2, T4, and P1 viruses were conducted with four different aluminum coagulants. The total infectious virus concentration in the suspension of floc particles that eventually formed by dosing with coagulant was measured after the floc particles were dissolved by raising the pH with an alkaline beef extract solution. The virus concentrations were extremely reduced after the water samples were dosed with aluminum coagulants. Viruses mixed with and adsorbed onto preformed aluminum hydroxide floc were, however, completely recovered after the floc dissolution. These results indicated that the aluminum coagulation process inactivates viruses. Virucidal activity was most prominent with the prehydrolyzed aluminum salt coagulant, polyaluminum chloride (PACl). Virucidal activity was lower in river water than in ultrapure water--natural organic matter in the river water depressed the virucidal activity. Mechanisms and kinetics of the virus inactivation were discussed. Our results suggest that intermediate polymers formed during hydrolysis of the aluminum coagulants sorbed strongly to viruses, either rendering them inactive or preventing infectivity. PMID:14655704

  10. Analysis of electrochemical noise for Type 410 stainless steel in chloride solutions

    SciTech Connect

    Kelly, R.G.; Inman, M.E.; Hudson, J.L.

    1996-12-31

    The electrochemical noise resulting from the corrosion of Type 410 stainless steel under open circuit conditions in solutions of widely different corrosivity has been examined. Parameters derived from electrochemical noise measurements and conventional electrochemical measurements were correlated with one another and with post-test examination on the specimens. Both the noise resistance and the polarization resistance increased with decreases in solution corrosivity. In all of the solutions studied, the noise resistance was found to be consistently higher than the polarization resistance. In solutions in which pitting occurred, the open circuit potential of the electrode versus a true reference electrode was more sensitive to the transition to stable pitting than was the pitting index.

  11. Corrosion cracking of 03N18K1M3TYu and 02N12Kh5M3 maraging steels in chloride solutions

    SciTech Connect

    Pavlov, V.N.; Chumalo, G.V.; Vereshchagin, A.N.; Melekhov, R.K.

    1987-07-01

    The authors investigate the electrochemical behavior in 0.5% NaCl solution and 42% MgCl/sub 2/ solution and the tendency toward corrosion cracking was determined in boiling 0.5% chloride solution of the cobalt-containing maraging steels in the title. Weld specimens and specimens of the base metal of 03N18K1M3TYu steel were tested in 3% NaCl solution for resistance to corrosion cracking. Additional investigations were made of specimens of that steel with previously created fatigue cracks of the base metal and the weld specimens in 3% NaCl solutions, since that steel is a promising material for structures operating in sea water and low concentration chloride solutions.

  12. Blue-Green Color Tunable Solution Processable Organolead Chloride-Bromide Mixed Halide Perovskites for Optoelectronic Applications.

    PubMed

    Sadhanala, Aditya; Ahmad, Shahab; Zhao, Baodan; Giesbrecht, Nadja; Pearce, Phoebe M; Deschler, Felix; Hoye, Robert L Z; Gödel, Karl C; Bein, Thomas; Docampo, Pablo; Dutton, Siân E; De Volder, Michael F L; Friend, Richard H

    2015-09-01

    Solution-processed organo-lead halide perovskites are produced with sharp, color-pure electroluminescence that can be tuned from blue to green region of visible spectrum (425-570 nm). This was accomplished by controlling the halide composition of CH3NH3Pb(BrxCl1-x)3 [0 ≤ x ≤ 1] perovskites. The bandgap and lattice parameters change monotonically with composition. The films possess remarkably sharp band edges and a clean bandgap, with a single optically active phase. These chloride-bromide perovskites can potentially be used in optoelectronic devices like solar cells and light emitting diodes (LEDs). Here we demonstrate high color-purity, tunable LEDs with narrow emission full width at half maxima (FWHM) and low turn on voltages using thin-films of these perovskite materials, including a blue CH3NH3PbCl3 perovskite LED with a narrow emission FWHM of 5 nm. PMID:26236949

  13. Thermodynamics of aqueous borate solutions I. Mixture of boric acid with sodium or potassium borate and chloride

    SciTech Connect

    Simonson, J.M.; Roy, R.N.; Roy, L.N.; Johnson, D.A.

    1987-10-01

    Potentials for the cell without liquid junction H/sub 2/, Ptlt. slashB(OH)/sub 3/(m/sub 1/),MB(OH)/sub 4/(m/sub 2/),MCl(m/sub 3/)lt. slashAgCl,Ag where M is sodium or potassium are reported over a range of ionic strength to I = 3 mol-kg/sup -1/ at 5 to 55/sup 0/C. Total boron concentration in the solutions was restricted to low levels to minimize formation of polynuclear boron species. Cell potentials are treated with the Pitzer ion interaction treatment for mixed electrolytes, with linear ionic strength dependence assumed for the activity coefficient of undissociated boric acid. Trace activity coefficients of sodium and potassium borates in chloride media are calculated at various temperatures.

  14. A conductivity study of unsymmetrical 2:1 type "complex ion" electrolyte: cadmium chloride in dilute aqueous solutions.

    PubMed

    Apelblat, Alexander; Esteso, Miguel A; Bešter-Rogač, Marija

    2013-05-01

    Systematic and precise measurements of electrical conductivities of aqueous solutions of cadmium chloride were performed in the 2 × 10(-5)-1 × 10(-2) mol·dm(-3) concentration range, from 278.15 to 313.15 K. Determined conductances were interpreted in terms of molecular model which includes a mixture of two 1:1 and 2:1 electrolytes. The molar limiting conductances of λ(0)(CdCl(+), T) and λ(0)(1/2Cd(2+), T), the equilibrium constants of CdCl(+) formation K(T) and the corresponding standard thermodynamic functions were evaluated using the Quint-Viallard conductivity equations, the Debye-Hückel equations for activity coefficients and the mass-action equation. An excellent agreement between calculated and experimental conductivities was reached. PMID:23534843

  15. Inhibition of Aluminum Oxyhydroxide Precipitation with Citric Acid

    SciTech Connect

    Dabbs, Daniel M.; Ramachandran, Usha; Lu, Sang; Liu, Jun; Wang, Li Q.; Aksay, Ilhan A.

    2005-12-06

    Citric acid has been shown to act as an agent for increasing the solubility of aluminum oxyhydroxides in aqueous solutions of high (>2.47 mol/mol) hydroxide-to-aluminum ratios. Conversely, citric acid also colloidally stabilizes particles in aqueous suspensions of aluminum-containing particles. Solutions of aluminum chloride, with and without citric acid added, were titrated with NaO(aq). The presence and size of particles were determined using quasi-elastic light scattering. In solutions that contained no citric acid, particles formed instantaneously when NaOH(aq) was added but these were observed to rapidly diminish in size, disappearing at OH/Al ratios below 2.5 mol/mol. When the OH/Al ratio was raised beyond 2.5 by addingmoreNaOH(aq), suspensions of colloidally stable particles formed. Large polycations containing 13 aluminum atoms were detected by 27Al solution NMR in citric-acid-free solutions with OH/Al ratios slightly lower than 2.5. In comparison, adding citric acid to solutions of aluminum chloride inhibited the formation of large aluminum-containing polycations. The absence of the polycations prevents or retards the subsequent formation of particles, indicating that the polycations, when present, act as seeds to the formation of new particles. Particles did not form in solutions with a citric acid/aluminum ratio of 0.8 until sufficient NaOH(aq) was added to raise the OH/Al ratio to 3.29. By comparison, lower amounts of citric acid did not prevent particles from forming but did retard the rate of growth.

  16. In situ LIF temperature measurements in aqueous ammonium chloride solution during uni-directional solidification

    NASA Astrophysics Data System (ADS)

    Shafii, M. Behshad; Lum, Chee L.; Koochesfahani, Manoochehr M.

    2010-04-01

    We present in situ whole-field measurements of the temperature field using laser-induced fluorescence in a study of bottom-chilled uni-directional solidification of aqueous ammonium chloride. We utilize a two-color, two-dye, ratiometric approach to address the significant spatial and temporal variations of laser sheet intensity field due to refractive index variations caused by the evolving concentration and temperature fields. In our work we take advantage of two temperature sensitive fluorescent dyes with opposite temperature sensitivities in order to increase the overall sensitivity and temperature resolution of the measurements. The resulting temperature sensitivity (about 4% K-1) is more than a factor of two higher than the original work of Sakakibara and Adrian (Exp Fluids 26:7-15, 1999) with a sensitivity 1.7% K-1. In situ measurements of the temperature field during solidification are presented, along with temperature characteristics of some of the complex flow features, such as plumes and fingers.

  17. An experimental determination of ferrous chloride and acetate complexation in aqueous solutions to 300[degrees]C

    SciTech Connect

    Palmer, D.A. ); Hyde, K.E. )

    1993-04-01

    Reliable thermodynamic information on the stability of ferrous chloride complexes at high temperatures is important to evaluations of iron transport in hydrothermal fluids, and to the power industry for iron corrosion and transport in the water/steam cycle. The formation of the monochloroiron(II) complex, FeCl[sup +], was studied potentiometrically from 125 to 295[degrees]C at 25 degree intervals at one molal ionic strength in aqueous solutions containing acetic acid, sodium acetate, and sodium trifluoromethanesulfonate. In this method, competition between chloride and acetate ions for the ferrous cation resulted in a change in solution pH, which in turn was monitored in situ in a hydrogen-electrode, concentration cell. A simple empirical approach was used to extrapolate these formation quotients to infinite dilution. The resulting constants proved to be in excellent agreement with previous spectrophotometric results obtained from 25 to 200[degrees]C. Thus, the present study confirms the validity of the conclusions made based on these earlier data concerning the solubility of Fe-containing minerals in hydrothermal brines. Formation constants at infinite dilution for FeCl[sup +] are compared with the stability of ferrous acetate and hydroxide complexes. The original potentiometric titration data for ferrous acetate complex formation were combined in a new fit with values determined from the present study at unit ionic strength. Two empirical treatments (namely the isocoulombic method and the temperature/water density function) were considered for fitting and extrapolating the infinite dilution formation constants to 350[degrees]C. 40 refs., 12 figs., 5 tabs.

  18. Interactions and aggregations in aqueous and brine solutions of poly(diallydimethylammonium chloride)/sodium bis(2-ethylhexyl) sulfosuccinate.

    PubMed

    Zheng, Peizhu; An, Xueqin; Peng, Xuhong; Shen, Weiguo

    2009-10-15

    The interactions between the anionic surfactant sodium bis(2-ethylhexyl) sulfosuccinate (AOT) and the polycation poly(diallydimethylammonium chloride) (PDDAC), the aggregations of AOT and PDDAC-bound AOT in PDDAC/AOT aqueous solutions, and the influence of salt on the interactions and aggregations have been studied by isothermal titration calorimetry (ITC), dynamic light scattering (DLS), and negative staining transmission electron microscopy (TEM). The adsorptions of AOT onto PDDAC and the formations of PDDAC-bound AOT micelles, free AOT micelles, and AOT vesicles were examined, and the corresponding critical concentrations were determined. Combining calculations of thermodynamic parameters with the above three experimental techniques, it was shown that the micellization of free AOT is driven by entropy gain, while the adsorption of AOT onto PDDAC and the micellization of PDDAC-bound AOT are driven by both enthalpy and entropy. It was also found that addition of salt enhances the binding of AOT onto PDDAC through the ion exchange and favors the formations of PDDAC/AOT micelles, free AOT micelles, and free AOT vesicles but prevents the transition of PDDAC/AOT micelles to the vesicles. Thermodynamic analysis suggested that the adsorption of AOT onto PDDAC and the micellization of PDDAC/AOT in PDDAC/AOT brine solutions are different in mechanism compared with that in corresponding aqueous solutions. PMID:19772316

  19. Alloy 22 Localized Corrosion Susceptibility In Aqueous Solutions Of Chloride And Nitrate Salts Of Sodium And Potassium At 110 - 150?C

    SciTech Connect

    Felker, S; Hailey, P D; Lian, T; Staggs, K J; Gdowski, G E

    2006-01-17

    Alloy 22 (a nickel-chromium-molybdenum-tungsten alloy) is being investigated for use as the outer barrier of waste containers for a high-level nuclear waste repository in the thick unsaturated zone at Yucca Mountain, Nevada. Experiments were conducted to assess crevice corrosion of Alloy 22 in de-aerated aqueous solutions of chloride and nitrate salts of potassium and sodium in the temperature range 110-150 C (some limited testing was also conducted at 90 C). Electrochemical tests were run in neutral salt solutions without acid addition and others were run in salt solutions with an initial hydrogen ion concentration of 10{sup -4} molal. The Alloy 22 specimens were weld prism specimens and de-aeration was performed with nitrogen gas. No evidence of crevice corrosion was observed in the range 125-150 C. In the 120 to 160 C temperature range, the anionic concentration of stable aqueous solutions is dominated by nitrate relative to chloride. At nominally 120 C, the minimum nitrate to chloride ratio is about 4.5, and it increases to about 22 at nominally 155 C. The absence of localized corrosion susceptibility in these solutions is attributed to the known inhibiting effect of the nitrate anion. At 110 C, aqueous solutions can have dissolved chloride in excess of nitrate. Localized corrosion was observed at nitrate to chloride ratios up to 1.0, the highest ratio tested. The extent of localized corrosion was confined to the crevice region of the samples, and was limited for nitrate to chloride ratios greater than or equal to 0.3. Aqueous solution chemistry studies indicate that nitrate to chloride ratios of less than 0.5 are possible for temperatures up to nominally 116 C. However, the exact upper temperature limit is unknown and no electrochemical testing was done at these temperatures. Limited comparison between 8 m Cl aqueous solutions of Na + K on the one hand and Ca on the other indicated similar electrochemical E{sub crit} values and similar morphology of attack

  20. Cooling and Freezing Behaviors of Aqueous Sodium Chloride Solution in a Closed Rectangular Container

    NASA Astrophysics Data System (ADS)

    Narumi, Akira; Kashiwagi, Takao; Nakane, Ichirou

    This paper investigates cooling and freezing behaviors of NaCl aqueous solution in a rectangular container equipped with horizontal partitions of micro porous film in order to determine the mechanisms of heat and mass transfer through cell wall for the purpose of freezing food. For comparison, experiments were performed using partitions of copper plate, no partition, and water. These processes were visualized and measured using real-time laser holographic interferometry. It was found that there was very little difference in the cooling process due to partitions, but that there were significant differences in freezing process when NaCl aqueous solution is used.

  1. Corrosion behavior of aluminum doped diamond-like carbon thin films in NaCl aqueous solution.

    PubMed

    Khun, N W; Liu, E

    2010-07-01

    Aluminum doped diamond-like carbon (DLC:Al) thin films were deposited on n-Si(100) substrates by co-sputtering a graphite target under a fixed DC power (650 W) and an aluminum target under varying DC power (10-90 W) at room temperature. The structure, adhesion strength and surface morphology of the DLC:Al films were characterized by X-ray photoelectron spectroscopy (XPS), micro-scratch testing and atomic force microscopy (AFM), respectively. The corrosion performance of the DLC:Al films was investigated by means of potentiodynamic polarization testing in a 0.6 M NaCl aqueous solution. The results showed that the polarization resistance of the DLC:Al films increased from about 18 to 30.7 k(omega) though the corrosion potentials of the films shifted to more negative values with increased Al content in the films. PMID:21128496

  2. Long-term cement-corrosion in chloride-rich solutions - a thermodynamic interpretation

    NASA Astrophysics Data System (ADS)

    Bube, C.; Metz, V.; Schild, D.; Bohnert, E.; Kienzler, B.

    2012-04-01

    Nuclear waste disposal relies on safe enclosure of radionuclides over long time-scales. Most experiments on interactions of radionuclides with barrier materials are running for several months, in some cases up to a few years. Very few experiments are available that confirm the results on longer time-scales and reassure that equilibrium conditions will be approached on the long term. This communication presents the latest results of full-scale cement corrosion experiments doped with uranium, which have been conducted for up to 22 years. Cemented waste simulates of 200L size were doped with Unat and exposed to MgCl2-rich or NaCl-saturated brine in the Asse salt mine (T = 28 ± 1 ° C). Solution composition and pH were monitored regularly. Some of the experiments were terminated in order to sample and analyze the solid phases. A geochemical code with a Pitzer database for high ionic strength systems is used to calculate the aqueous and solid phases expected at equilibrium conditions. In order to evaluate the thermodynamic database for the cementitious system, calculated solid phases and solution compositions were additionally compared to results of laboratory experiments on cement corrosion in MgCl2-rich solutions with mass to volume ratios (m/V) between 0.025 and 1.0. Solid and solution composition of the laboratory experiments after ~3 years agree well with results predicted from the thermodynamic calculations. With increasing m/V, transformation of the initial MgCl2-rich solutions into CaCl2-rich solutions is observed. This exchange reaction of Mg from the solution against Ca in the cement leads to a pHm (-log[H+]) increase up to 12 (from initial values around 9). Major solid phases found by analytical methods are also obtained in the calculations (e.g. gypsum, calcite, hydrotalcite / friedel's salt, brucite). Discrepancies are caused by various amorphous phases, which cannot be represented in the database. In the full-scale experiments (with m/V around 2.7), a

  3. Method for calcining nuclear waste solutions containing zirconium and halides

    DOEpatents

    Newby, Billie J.

    1979-01-01

    A reduction in the quantity of gelatinous solids which are formed in aqueous zirconium-fluoride nuclear reprocessing waste solutions by calcium nitrate added to suppress halide volatility during calcination of the solution while further suppressing chloride volatility is achieved by increasing the aluminum to fluoride mole ratio in the waste solution prior to adding the calcium nitrate.

  4. Electrochemical Study of Corrosion Behavior of Wrought Stellite Alloys in Sodium Chloride and Green Death Solutions

    NASA Astrophysics Data System (ADS)

    Zhang, X. Z.; Liu, R.; Chen, K. Y.; Yao, M. X.; Collier, R.

    2015-09-01

    Corrosion behavior of wrought Stellite 6B and Stellite 6K, which have similar chemical composition but contain different carbon content, in 3.5 wt.% NaCl solution and in Green Death solution is investigated using various electrochemical methods, including potentiodynamic polarization, cyclic polarization, and electrochemical impedance spectroscopy (EIS). The obtained potentiodynamic polarization curves, cyclic polarization curves, and EIS spectra for these alloys are in good agreement, showing that Stellite 6K with higher carbon content is easier corroded due to its larger volume fraction of carbides but the Cr2O3 film formed on this alloy is stronger and more stable than that on Stellite 6B. Further immersion tests on these alloys show that Stellite 6K has less resistance to pitting corrosion.

  5. Hydrometallurgical extraction of zinc from CaO treated EAF dust in ammonium chloride solution.

    PubMed

    Miki, Takahiro; Chairaksa-Fujimoto, Romchat; Maruyama, Katsuya; Nagasaka, Tetsuya

    2016-01-25

    Zinc in Electric Arc Furnace dust or EAF dust mainly exists as ZnFe2O4 and ZnO. While ZnO can be simply dissolved into either an acidic or alkaline solution, it is difficult to dissolve ZnFe2O4. In our previous work, we introduced a process called "CaO treatment", a preliminary pyrometallurgical process designed to transform the ZnFe2O4 in the EAF dust into ZnO and Ca2Fe2O5. The halogens and others heavy metals were favorably vaporized during CaO treatment with no essential evaporation loss of zinc and iron, leaving CaO treated dust which consisted mainly of ZnO and Ca2Fe2O5 and no problematic ZnFe2O4 compound. In this work, the selective leaching of zinc over iron and calcium in the CaO treated dust was investigated using an NH4Cl solution. The effects of temperature, reaction time and NH4Cl concentration on dissolution behavior were examined. While most of the zinc in the CaO treated dust was extracted after 2 h at 70 °C with 2 M NH4Cl, only about 20% of calcium was leached in NH4Cl solution. However, the iron did not dissolve and remained as Ca2Fe2O5 in residue. It was confirmed that zinc can be effectively recovered using NH4Cl solution. PMID:26448494

  6. Corrosion of iron, aluminum and copper-base alloys in glycols under simulated solar collector conditions

    SciTech Connect

    Beavers, J.A.; Diegle, R.B.

    1981-10-01

    The corrosion behavior of iron, aluminum and copperbase alloys was studied in uninhibited glycol solutions under conditions that simulate those found in non-concentrating solar collectors. It was found that only Type 444 stainless steel exhibited adequate corrosion resistance; there was no evidence of pitting, crevice corrosion, or galvanic attack, and general corrosion rates were low. The general corrosion rate of CDA 122 copper was high (greater than 200 ..mu..m/y) under some test conditions, but copper was resistant to pitting and crevice attack. General corrosion rates of the aluminum alloys (1100, 3003 and 6061) were low, but these alloys were susceptible to pitting and crevice attack. The propensity for pitting was greatest in the presence of chlorides but it also was severe in the absence of chlorides following long exposures. The onset of pitting of the aluminum alloys in chloride-free solutions was attributed to degradation of the glycols.

  7. Saturated sodium chloride solution under an external static electric field: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Ren, Gan; Wang, Yan-Ting

    2015-12-01

    The behavior of saturated aqueous NaCl solutions under a constant external electric field (E) was studied by molecular dynamics (MD) simulation. Our dynamic MD simulations indicated that the irreversible nucleation process towards crystallization is accelerated by a moderate E but retarded or even prohibited under a stronger E, which can be understood by the competition between self-diffusion and drift motion. The former increases with E, thereby accelerating the nucleation process, whereas the latter pulls oppositely charged ions apart under a stronger E, thereby decelerating nucleation. Additionally, our steady-state MD simulations indicated that a first-order phase transition occurs in saturated solutions at a certain threshold Ec. The magnitude of Ec increases with concentration because larger clusters form more easily when the solution is more concentrated and require a stronger E to dissociate. Project supported by the National Basic Research Program of China (Grant No. 2013CB932804) and the National Natural Science Foundation of China (Grant Nos. 91227115, 11274319, and 11421063).

  8. An experimental determination of ferrous chloride and acetate complexation in aqueous solutions to 300°C

    NASA Astrophysics Data System (ADS)

    Palmer, Donald A.; Hyde, K. E.

    1993-04-01

    The formation of the monochloroiron(II) complex, FeCl +, was studied potentiometrically from 125 to 295°C at 25 degree intervals at one molal ionic strength in aqueous solutions containing acetic acid, sodium acetate, and sodium trifluoromethanesulfonate. In this method, competition between chloride and acetate ions for the ferrous cation resulted in a change in solution pH, which in turn was monitored in situ in a hydrogen-electrode, concentration cell. A simple empirical approach was used to extrapolate these formation quotients to infinite dilution. The resulting constants proved to be in excellent agreement with previous spectrophotometric results obtained from 25 to 200°C. Thus, the present study confirms the validity of the conclusions made based on these earlier data concerning the solubility of Fe-containing minerals in hydrothermal brines. Formation constants at infinite dilution for FeCl + are compared with the stability of ferrous acetate and hydroxide complexes. The original potentiometric titration data for ferrous acetate complex formation were combined in a new fit with values determined from the present study at unit ionic strength. Two empirical treatments (namely the isocoulombic method and the temperature/water density function) were considered for fitting and extrapolating the infinite dilution formation constants to 350°C.

  9. Study of benzotriazole as corrosion inhibitors of carbon steel in chloride solution containing hydrogen sulfide using electrochemical impedance spectroscopy (EIS)

    SciTech Connect

    Solehudin, Agus; Nurdin, Isdiriayani

    2014-03-24

    Corrosion and inhibition studies on API 5LX65 carbon steel in chloride solution containing various concentrations of benzotriazole has been conducted at temperature of 70°C using Electrochemical Impedance Spectroscopy (EIS). Corroded carbon steel surface with and without inhibitor have been observed using X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Energy Dispersive Spectroscopy (EDS). The objectives of this research are to study the performance of benzotriazole as corrosion inhibitors. The experimental results of carbon steel corrosion in 3.5% NaCl solution containing 500 mg/l H{sub 2}S at different BTAH concentrations showed that corrosion rate of carbon steel decreases with increasing of BTAH concentrations from 0 to 10 mmol/l. The inhibition efficiency of BTAH was found to be affected by its concentration. The optimum efficiency obtained of BTAH is 93% at concentration of 5 mmol/l. The result of XRD and EDS analysis reveal the iron sulfide (FeS) formation on corroded carbon steel surface without inhibitor. The EDS spectrum show the Nitrogen (N) bond on carbon steel surface inhibited by BTAH.

  10. Study of benzotriazole as corrosion inhibitors of carbon steel in chloride solution containing hydrogen sulfide using electrochemical impedance spectroscopy (EIS)

    NASA Astrophysics Data System (ADS)

    Solehudin, Agus; Nurdin, Isdiriayani

    2014-03-01

    Corrosion and inhibition studies on API 5LX65 carbon steel in chloride solution containing various concentrations of benzotriazole has been conducted at temperature of 70°C using Electrochemical Impedance Spectroscopy (EIS). Corroded carbon steel surface with and without inhibitor have been observed using X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Energy Dispersive Spectroscopy (EDS). The objectives of this research are to study the performance of benzotriazole as corrosion inhibitors. The experimental results of carbon steel corrosion in 3.5% NaCl solution containing 500 mg/l H2S at different BTAH concentrations showed that corrosion rate of carbon steel decreases with increasing of BTAH concentrations from 0 to 10 mmol/l. The inhibition efficiency of BTAH was found to be affected by its concentration. The optimum efficiency obtained of BTAH is 93% at concentration of 5 mmol/l. The result of XRD and EDS analysis reveal the iron sulfide (FeS) formation on corroded carbon steel surface without inhibitor. The EDS spectrum show the Nitrogen (N) bond on carbon steel surface inhibited by BTAH.

  11. Dissociation of hydrophobic and charged nano particles in aqueous guanidinium chloride and urea solutions: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Li, Weifeng; Mu, Yuguang

    2012-02-01

    It has been a long history that urea and guanidinium chloride (GdmCl) are used as agents for denaturing proteins. The underlying mechanism has been extensively studied in the past several decades. However, the question regarding why GdmCl is much stronger than urea has seldom been touched. Here, through molecular dynamics simulations, we show that a 4 M GdmCl solution is more able than 7 M urea solution to dissociate both hydrophobic and charged nano-particles (NP). Both urea and GdmCl affect the NPs' aggregation through direct binding to the NP surface. The advantages of GdmCl originate from the net charge of bound guanidinium ions which can generate a local positively charged environment around hydrophobic and negatively charged NPs. This effective coating can introduce Coulombic repulsion between all the NPs. Urea shows certain ability to dissociate hydrophobic NPs. However, in the case of charged NPs, urea molecules located between two opposite-charged NPs will form ordered hydrogen bonds, acting like ``glue'' which prevents separation of the NPs. Although urea can form hydrogen bonds with either hydrophilic amino acids or the protein backbone, which are believed to contribute to protein denaturation, our findings strongly suggest that this property does not always contribute positively to urea's denaturation power.

  12. Inefficacy of osmotic backwash induced by sodium chloride salt solution in controlling SWRO membrane fouling

    NASA Astrophysics Data System (ADS)

    Farooque, A. Mohammed; Al-Jeshi, Subhi; Saeed, Mohamed O.; Alreweli, Ali

    2014-12-01

    A study was conducted to evaluate the efficacy of osmotic backwash induced by high salt (NaCl) concentration solution on feed side of seawater reverse osmosis (SWRO) membranes, online and offline, in controlling membrane fouling and therefore minimizing/eliminating the need for chemical cleaning. SWRO membranes were deliberately fouled by feeding seawater from an open intake located on the Arabian Gulf Coast without dosing chemicals. The fouled membranes were subjected to offline cleaning with the salt solution of up to 25 % concentration. Despite the partial removal of foulants from the membrane surface, SWRO membrane performance could not be restored, indicating the ineffectiveness of osmotic backwash in aiding offline salt cleaning. Similarly, online osmotic backwash was found to be not only ineffective in removing foulants from membrane surfaces but actually increased the fouling rate, as indicated by faster fouling rates compared to other cases. Although the driving force required for the osmotic backwash existed, the generated back flow proved to be insufficient to detach foulants from membrane surfaces. During the study period, the average SWRO membrane flux was maintained between 19 and 23 LMH, whereas the average generated back flow flux by high salt concentration solution was only 11 LMH, which was not adequate to remove foulants from membrane surfaces. Moreover, it seems that the membrane configuration as well as inherent microstructure of SWRO membrane places certain constraints on the osmotic backwash process and renders osmotic backwash ineffective in tackling SWRO membrane fouling. Hence, chemical cleaning is essential to restore SWRO membrane performance whenever fouling occurs, and the use of highly concentrated salt solution does not have any significant benefit. Membrane autopsy revealed only an insignificant accumulation of biofouling layer despite the absence of disinfection. However, it was shown that culturable biofilm bacteria species

  13. Correlations between structure, spectra, and thermodynamics in solutions of cobalt chloride in sodium tetrachloroaluminates

    SciTech Connect

    Newman, D.S.; Tumidajski, P.J.; Blander, M.

    1990-01-01

    An EMF technique using the cell Co/CoCl{sub 2} {minus} Na AlCl{sub 4}//(AgCl)x {minus} NaAlCl{sub 4} (x fixed)/Ag was used to measure the solubility of CoCl{sub 2} in NaCl{center dot}AlCl{sub 3} melts. The changes in EMF as a function of changes in melt composition were correlated with changes in the UV-Vis spectra of the dissolved cobalt species. From these data the microscopic structural contributions to the macroscopic thermodynamic properties of the solutions were estimated. 14 refs., 5 figs., 1 tab.

  14. Electrochemical corrosion and modeling studies of types 7075 and 2219 aluminum alloys in a nitric acid + ferric sulfate deoxidizer solution

    NASA Astrophysics Data System (ADS)

    Savas, Terence P.

    The corrosion behavior of types 7075-T73 and 2219-T852 high strength aluminum alloys have been investigated in a HNO3 + Fe2(SO 4)3 solution. The materials are characterized in the time domain using the electrochemical noise resistance parameter (Rn) and in the frequency-domain using the spectral noise impedance parameter ( Rsn). The Rsn parameter is derived from an equivalent electrical circuit model that represents the corrosion test cell schematic used in the present study. These calculated parameters are correlated to each other, and to corresponding scanning electron microscopy (SEM) examinations of the corroded surfaces. In addition, energy dispersive spectroscopy (EDS) spectra are used in conjunction with SEM exams for particle mapping and identification. These constituent particles are characterized with respect to their size and composition and their effect on the localized corrosion mechanisms taking place. Pitting mechanisms are identified as 'circumferential' where the particles appeared noble with respect to the aluminum matrix and by 'selective dissolution' where they are anodic to the aluminum matrix. The electrochemical data are found to be in good agreement with the surface examinations. Specifically, the electrochemical parameters Rn and Rsn were consistent in predicting the corrosion resistance of 7075-T73 to be lower than for the 2219-T852 alloy. Other characteristic features used in understanding the corrosion mechanisms include the open circuit potential (OCP) and coupling-current time records.

  15. Corrosion Fatigue Behavior of 316LN SS in Acidified Sodium Chloride Solution at Applied Potential

    NASA Astrophysics Data System (ADS)

    Poonguzhali, A.; Pujar, M. G.; Mallika, C.; Mudali, U. Kamachi

    2015-05-01

    The influence of acidified 1 M NaCl solution by addition of 2 ml/L of HCl on the cyclic plastic deformation of AISI Type 316LN SS containing 0.07 wt.% and 0.22 wt.% N was investigated as a function of the applied potentials. The corrosion fatigue (CF) behavior of stainless steel (SS) was explained vis-a-vis the dislocation behavior, the propensity to form microcracks, and the evolution of the current transients based on the studies carried out at both room-temperature and boiling conditions. CF experiments were conducted using round tensile specimens at a stress ratio of 0.5 and a frequency of 0.1 Hz. Two different kinds of damage mechanisms were observed (I) the damage mechanism in the stable-passive state was correlated with the localization of the anodic dissolution due to a depassivation-repassivation process, whereas (II) the cyclic stress induced pitting corrosion in the metastable pitting state, which resulted in formation of microcracks. The study of the microcracking process and its evolution is a key to the physical mechanism by which the fatigue life of stainless steels would be affected in an aqueous corrosive solution under the applied potential.

  16. Atomic force microscopy observations of pitting corrosion and inhibition on 7075-T651 aluminum alloy in hydrochloric acid solutions

    SciTech Connect

    Josefowicz, J.Y.; Farrington, G.C.; DeLuccia, J.J.; Agarwala, V.S.

    1995-03-01

    Atomic force microscopy, a unique surface imaging technique that enables the effects of an imposed environment on the substrate to be measured and assessed, was used to define the effects of a dilute aqueous hydrochloric acid solution (0.03 N) on a polished and etched surface of a peak aged aluminum-zinc-magnesium alloy (7075-T651). A multifunctional corrosion inhibitor with dichromate, nitrite, borate, and molybdate ions, especially solubilized in an organic medium, was introduced to the study and its corrosion retardation effects were observed in situ by the atomic force microscope.

  17. Separation of mercury from aqueous mercuric chloride solutions by onion skins

    SciTech Connect

    Asai, S.; Konishi, Y.; Tomisaki, H.; Nakanishi, M.

    1986-01-01

    The separation of mercury from aqueous HgCl/sub 2/ solutions by onion skins (outermost coat) was studied both experimentally and theoretically. The distribution equilibria were measured by the batchwise method. The experimental results revealed that onion skin is a useful material for separating mercury from aqueous systems. The distribution data obtained at 25/sup 0/C were analyzed by using the theory based on the law of mass action. The separation of dissolved mercury by onion skins was found to be a process accompanied by an ion-exchange reaction of the cationic complex HgCl/sup +/ and an adsorption of the neutral complex HgCl/sub 2/. The equilibrium constants of the ion-exchange and adsorption processes at 25/sup 0/C and the mercury-binding capacity of onion skins were determined. Further, it was found that the distribution equilibrium of mercury is comparatively insensitive to temperature.

  18. Corrosion Behavior of Stainless Steels in Neutral and Acidified Sodium Chloride Solutions by Electrochemical Impedance Spectroscopy

    NASA Technical Reports Server (NTRS)

    Calle, L. M.; Kolady, M. R.; Vinje, R. D.

    2004-01-01

    The objective of this work was to evaluate the corrosion performance of three alloys by Electrochemical Impedance Spectroscopy (EIS) and to compare the results with those obtained during a two-year atmospheric exposure study.' Three alloys: AL6XN (UNS N08367), 254SM0 (UNS S32154), and 304L (UNS S30403) were included in the study. 304L was included as a control. The alloys were tested in three electrolyte solutions which consisted of neutral 3.55% NaC1, 3.55% NaC1 in 0.lN HC1, and 3.55% NaC1 in 1.ON HC1. These conditions were expected to be less severe, similar, and more severe respectively than the conditions at NASA's Kennedy Space Center launch pads.

  19. Influence of microstructure on the corrosion resistance of AISI type 304L and type 316L sintered stainless steels exposed to ferric chloride solution

    SciTech Connect

    Otero, E.; Pardo, A.; Utrilla, M.V.; Perez, F.J.; Saenz, E.

    1995-10-01

    The corrosion behavior of type 304L and type 316L austenitic stainless steels, produced by powder metallurgy, when exposed to a ferric chloride solution was studied. The exposures were conducted according to ASTM G48-76, Method A. The influence of ferric chloride concentration and exposure temperature on the corrosion kinetics of these materials was evaluated. A mechanism is proposed to explain the associated morphology observed in the microstructures produced after exposure of these P/M alloys to the aggressive medium.

  20. Environmentally Assisted Cracking of Alloy 7050-T7451 Exposed to Aqueous Chloride Solutions

    NASA Astrophysics Data System (ADS)

    Braun, Reinhold

    2016-03-01

    The stress corrosion cracking (SCC) behavior of 7050-T7451 plate material was investigated in short-transverse direction performing constant load and constant extension rate tests. Smooth and notched tensile specimens were permanently immersed in substitute ocean water and in an aqueous solution of 0.6 M NaCl + 0.06 M (NH4)2SO4. Alloy 7050-T7451 exhibited high SCC resistance in both synthetic environments. However, conducting cyclic loading tests, environment-induced cracking was observed. Applying a sawtooth waveform, notched tensile specimens were strained under constant load amplitude conditions at constant displacement rates ranging from 2 × 10-6 to 2 × 10-4 mms-1. The stress ratio R = σ min/ σ max was 0.1 with maximum stresses of 300 and 400 MPa. When cyclically loaded in substitute ocean water, notched specimens failed predominantly by transgranular environment-induced cracking. Striations were observed on the cleavage-like facets. The number of cycles-to-failure decreased with decreasing displacement rate. A slope of 0.5 was obtained by fitting the logarithmic plot of number of cycles-to-failure vs nominal loading frequency, indicating a hydrogen embrittlement mechanism controlled by diffusion.

  1. Structural characterization of zinc(II) chloride in aqueous solution and in the protic ionic liquid ethyl ammonium nitrate by x-ray absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    D'Angelo, Paola; Zitolo, Andrea; Ceccacci, Francesca; Caminiti, Ruggero; Aquilanti, Giuliana

    2011-10-01

    Extended x-ray absorption fine structure (EXAFS) spectroscopy has been used to investigate the species and structures existing in a series of ZnCl2-H2O-NaCl solutions with different chloride/zinc ratios and in a solution of ZnCl2 in the protic ionic liquid ethyl ammonium nitrate (EAN). The average coordination numbers and distances of zinc species were determined from the analysis of the EXAFS data. In aqueous solution the number of chloride ions tightly bounded to Zn2+ is significantly related to the chloride/zinc ratio, and no inner complex formation between Zn2+ and Cl- ions has been detected for low ZnCl2 concentration (0.1 and 0.2 M). Conversely, in the same concentration range (0.13 M) the ZnCl2 species do not dissociate in EAN and the Zn2+ first coordination shell has two chloride ions and is completed by two oxygen atoms of the nitrate anion. The results of this investigation show that notwithstanding the existence of similar characteristics between EAN and water, the solvation properties of the two solvents are markedly different.

  2. The effect of initial tonicity on freeze/thaw injury to human red cells suspended in solutions of sodium chloride.

    PubMed

    Pegg, D E; Diaper, M P

    1991-02-01

    Human red blood cells, suspended in solutions of sodium chloride, have been frozen to temperatures between -2 and -14 degrees C and thawed, and the extent of hemolysis was measured. In parallel experiments, red cells were exposed to similar cycles of change in the composition of the suspending solution, but by dialysis at 21 degrees C. The tonicity of the saline in which the cells were initially suspended was varied between 0.6x isotonic and 4x isotonic; some samples from each experimental treatment were returned to isotonic saline before hemolysis was measured. It was found that the tonicity of the saline used to suspend the cells for the main body of the experiment affected the amount of hemolysis measured: raising the tonicity from 0.6x to 1x to 2x reduced hemolysis, both in the freezing and in the dialysis experiments, whereas raising the tonicity further to 4x reversed that trend. There was little difference between the freeze/thaw and the dialysis treatments for the cells suspended in 1x or 2x saline, whether or not the cells were returned to isotonic conditions. However, the cells suspended in 0.6x saline showed greater damage from freezing and thawing than from the comparable change in the composition of the solution, whether or not they were returned to isotonic conditions. Cells that were suspended in 4x saline and exposed to changes in salt concentration by dialysis showed less hemolysis when they were assayed in the 4x solution than cells that had received the comparable freezing/thaw treatment, but when the experiment included a return to isotonicity, the two treatments gave similar results. Returning the cells to isotonic saline had a negligible affect on the cells in 0.6x and 1x saline, but caused considerable hemolysis in the 2x and 4x samples, more so after dialysis than after freezing and thawing. We conclude that cells suspended in 0.6x and 4x saline behave differently from cells suspended in 1x and 2x saline and hence that cells suspended in a

  3. Re-passivation Potential of Alloy 22 in Chloride plus Nitrate Solutions using the Potentiodynamic-Galvano-static-Potentiostatic Method

    SciTech Connect

    Evans, Kenneth J.; Rebak, Raul B.

    2007-07-01

    In general, the susceptibility of Alloy 22 to suffer crevice corrosion is measured using the Cyclic Potentiodynamic Polarization (CPP) technique. This is a fast technique that gives rather accurate and reproducible values of re-passivation potential (ER1) in most cases. In the fringes of susceptibility, when the environment is not highly aggressive, the values of re-passivation potential using the CPP technique may not be highly reproducible, especially because the technique is fast. To circumvent this, the re-passivation potential of Alloy 22 was measured using a slower method that combines Potentiodynamic-Galvano-static-Potentiostatic steps (called here the Tsujikawa-Hisamatsu Electrochemical or THE method). The THE method applies the charge to the specimen in a more controlled way, which may give more reproducible re-passivation potential values, especially when the environment is not aggressive. The values of re-passivation potential of Alloy 22 in sodium chloride plus potassium nitrate solutions were measured using the THE and CPP methods. Results show that both methods yield similar values of re-passivation potential, especially under aggressive conditions. (authors)

  4. A new dioxime corrosion inhibitor for the protection and conservation of copper: synthesis, characterization and evaluation in acidic chloride solution

    NASA Astrophysics Data System (ADS)

    Abu-Baker, Ahmad N.; Al-Qudah, Mahmoud A.

    2016-08-01

    This study aimed to investigate a new dioxime compound as a corrosion inhibitor for copper. The compound (4,6-dihydroxy benzene-1,3-dicarbaldehyde dioxime) was synthesized and characterized by nuclear magnetic resonance spectroscopy. Electrochemical impedance spectroscopy and potentiodynamic polarization measurements were used to compare the dioxime compound with benzotriazole for their effectiveness as corrosion inhibitors for copper in 0.1 M HCl solution. Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) were used to investigate the bonding mechanisms and morphological changes of the two inhibitors on the copper surface. The electrochemical techniques showed that the new dioxime compound was more effective than benzotriazole in inhibiting copper corrosion in the acidic chloride medium. The FTIR and SEM results indicated that the dioxime compound was able to coordinate with copper ions and formed a protective film on the copper surface. It was concluded that the new dioxime compound proved effectiveness to be used as a corrosion inhibitor for the protection and conservation of copper.

  5. Studies of removal of palladium(II) ions from chloride solutions on weakly and strongly basic anion exchangers.

    PubMed

    Hubicki, Z; Wołowicz, A; Leszczyńska, M

    2008-11-30

    Palladium and its compounds find wide application in industry as a catalytic agent in different manufacture processes. Recovery of precious metals from industrial wastes is difficult and time consuming but in spite of these disadvantages it becomes profitable. Palladium(II) ions sorption from various chloride solutions of the composition: 0.1-6.0M HCl-0.00056 M Pd(II), 1.0M ZnCl(2)-0.1M HCl-0.00056 M Pd(II), 1.0M AlCl(3)-0.1M HCl-0.00056 M Pd(II) on the weakly and strongly basic anion exchangers (Varion ATM, Varion ADM and Varion ADAM) was discussed. The sorption research of Pd(II) ions on these resins was carried out by means of static and dynamic methods. The dynamic processes were applied in order to determine the breakthrough curves of Pd(II) ions. Moreover, the working ion-exchange capacities as well as the weight and bed distribution coefficients were determined from the Pd(II) breakthrough curves. The recovery factors of Pd(II) ions (% R) depending on the phase contact time were obtained by means of static methods. The highest ion-exchange capacities for the 0.1-6.0M HCl-0.00056 M Pd(II) systems were obtained for the weakly basic ion-exchange resin Varion ADAM. PMID:18358602

  6. Chloride as tracer of solute transport in the aquifer-aquitard system in the Pearl River Delta, China

    NASA Astrophysics Data System (ADS)

    Kuang, Xingxing; Jiao, Jiu Jimmy; Wang, Ya

    2016-02-01

    A 1D numerical model is constructed to investigate the impact of sedimentation and sea level changes on transport of Cl- in the aquifer-aquitard system in the Pearl River Delta (PRD), China. The model simulates the evolution of the vertical Cl- concentration profiles during the Holocene. Sedimentation is modeled as a moving boundary problem. Chloride concentration profiles are reconstructed for nine boreholes, covering a wide area of the PRD, from northwest to southeast. Satisfactory agreement is obtained between simulated and measured Cl- concentration profiles. Diffusion solely is adequate to reproduce the vertical Cl- concentration profiles, which indicates that diffusion is the regionally dominant vertical transport mechanism across the aquitards in the PRD. The estimated effective diffusion coefficients of the aquitards range from 2.0 × 10-11 to 2.0 × 10-10 m2/s. The effective diffusion coefficients of the aquifers range from 3.0 × 10-11 to 4.0 × 10-10 m2/s. Advective transport tends to underestimate Cl- concentrations in the aquitard and overestimate Cl- concentrations in the basal aquifer. The results of this study will help understand the mechanisms of solute transport in the PRD and other deltas with similar geological and hydrogeological characteristics.

  7. Chloride as tracer of solute transport in the aquifer-aquitard system in the Pearl River Delta, China

    NASA Astrophysics Data System (ADS)

    Kuang, Xingxing; Jiao, Jiu Jimmy; Wang, Ya

    2016-08-01

    A 1D numerical model is constructed to investigate the impact of sedimentation and sea level changes on transport of Cl- in the aquifer-aquitard system in the Pearl River Delta (PRD), China. The model simulates the evolution of the vertical Cl- concentration profiles during the Holocene. Sedimentation is modeled as a moving boundary problem. Chloride concentration profiles are reconstructed for nine boreholes, covering a wide area of the PRD, from northwest to southeast. Satisfactory agreement is obtained between simulated and measured Cl- concentration profiles. Diffusion solely is adequate to reproduce the vertical Cl- concentration profiles, which indicates that diffusion is the regionally dominant vertical transport mechanism across the aquitards in the PRD. The estimated effective diffusion coefficients of the aquitards range from 2.0 × 10-11 to 2.0 × 10-10 m2/s. The effective diffusion coefficients of the aquifers range from 3.0 × 10-11 to 4.0 × 10-10 m2/s. Advective transport tends to underestimate Cl- concentrations in the aquitard and overestimate Cl- concentrations in the basal aquifer. The results of this study will help understand the mechanisms of solute transport in the PRD and other deltas with similar geological and hydrogeological characteristics.

  8. Effects of solution pH and synthetic method on destabilization process of polytitanium-silicate-chloride.

    PubMed

    Huang, Xin; Gao, Baoyu; Sun, Yangyang; Yue, Qinyan; Wang, Yan; Li, Qian

    2016-07-01

    Effect of solution pH on coagulation performance and flock properties of a novel inorganic polymer coagulant-polytitanium-silicate-chloride (PTSC) in humic acid-kaolin water treatment was investigated in this work. PTSC was synthesized by two approaches: composite and co-complexion, denoted as PTSCm and PTSCc respectively. The effect of the synthetic method was also considered. Results indicated that turbidity and DOM removal were improved by addition of polysilicic acid, especially under acidic condition. PTSCc achieved slightly better DOM removal than that of PTSCm. Flocks formed under acidic condition was smaller than those form under alkaline condition. In addition, flocks formed by PTSCc were larger than PTSCm flocks. Results also indicated that flock strength and recovery ability was slightly improved by the addition of PSiA. Moreover, under acidic condition, PTSC flocks had larger fractal dimension with more compact structure, especially for PTSCm flocks. In contrast, they were looser compared with PTC flock, especially for PTSCm flocks under neutral and alkaline conditions. PMID:26994354

  9. Removal of malachite green dye from aqueous solution using mesoporous silica synthesized from 1-octyl-3-methylimidazolium chloride ionic liquid

    NASA Astrophysics Data System (ADS)

    Ekka, Basanti; Nayak, Soumitra Ranjan; Dash, Priyabrat; Patel, Raj Kishore

    2016-04-01

    In this research, mesoporous silica was synthesized via a modified sol-gel route using 1-octyl-3-methylimidazolium chloride and was employed to remove malachite green (MG) dye from aqueous solution. Subsequently, this material was characterized and identified by different techniques such as Fourier transform infrared spectroscopy (FT-IR), N2 adsorption-desorption method, scanning electron microscopy (SEM), and thermosgravimetric analysis (TGA). Unique properties such as high surface area and pore diameter, in addition to highly reactive atoms and presence of various functional groups make the mesoporous silica possible for efficient removal of malachite green (MG). In batch experimental set-up, optimum conditions for quantitative removal of MG by mesoporous silica was attained by varying different variables such as adsorbent dosage, initial dye concentration, contact time, and pH. Optimum values were set as pH of 8.0, 0.5 g of adsorbent at contact time of 120 min. The adsorption of MG follows the pseudo-second-order rate equation. Equilibrium data fitted well with the Freundlich model at all amount of adsorbent, while maximum adsorption capacity was 5.981 mg g-1 for 0.5 g mesoporous silica synthesized in IL.

  10. Aluminum reference electrode

    DOEpatents

    Sadoway, Donald R.

    1988-01-01

    A stable reference electrode for use in monitoring and controlling the process of electrolytic reduction of a metal. In the case of Hall cell reduction of aluminum, the reference electrode comprises a pool of molten aluminum and a solution of molten cryolite, Na.sub.3 AlF.sub.6, wherein the electrical connection to the molten aluminum does not contact the highly corrosive molten salt solution. This is accomplished by altering the density of either the aluminum (decreasing the density) or the electrolyte (increasing the density) so that the aluminum floats on top of the molten salt solution.

  11. Aluminum reference electrode

    DOEpatents

    Sadoway, D.R.

    1988-08-16

    A stable reference electrode is described for use in monitoring and controlling the process of electrolytic reduction of a metal. In the case of Hall cell reduction of aluminum, the reference electrode comprises a pool of molten aluminum and a solution of molten cryolite, Na[sub 3]AlF[sub 6], wherein the electrical connection to the molten aluminum does not contact the highly corrosive molten salt solution. This is accomplished by altering the density of either the aluminum (decreasing the density) or the electrolyte (increasing the density) so that the aluminum floats on top of the molten salt solution. 1 fig.

  12. Aluminum-doped ceria-zirconia solid solutions with enhanced thermal stability and high oxygen storage capacity

    PubMed Central

    2012-01-01

    A facile solvothermal method to synthesize aluminum-doped ceria-zirconia (Ce0.5Zr0.5-xAlxO2-x/2, x = 0.1 to 0.4) solid solutions was carried out using Ce(NH4)2(NO3)6, Zr(NO3)3·2H2O Al(NO3)3·9H2O, and NH4OH as the starting materials at 200°C for 24 h. The obtained solid solutions from the solvothermal reaction were calcined at 1,000°C for 20 h in air atmosphere to evaluate the thermal stability. The synthesized Ce0.5Zr0.3Al0.2O1.9 particle was characterized for the oxygen storage capacity (OSC) in automotive catalysis. For the characterization, X-ray diffraction, transmission electron microscopy, and the Brunauer-Emmet-Teller (BET) technique were employed. The OSC values of all samples were measured at 600°C using thermogravimetric-differential thermal analysis. Ce0.5Zr0.3Al0.2O1.9 solid solutions calcined at 1,000°C for 20 h with a BET surface area of 18 m2 g−1 exhibited a considerably high OSC of 427 μmol-O g−1 and good OSC performance stability. The same synthesis route was employed for the preparation of the CeO2 and Ce0.5Zr0.5O2. The incorporation of aluminum ion in the lattice of ceria-based catalyst greatly enhanced the thermal stability and OSC. PMID:23025588

  13. Aqueous combustion synthesis of aluminum oxide thin films and application as gate dielectric in GZTO solution-based TFTs.

    PubMed

    Branquinho, Rita; Salgueiro, Daniela; Santos, Lídia; Barquinha, Pedro; Pereira, Luís; Martins, Rodrigo; Fortunato, Elvira

    2014-11-26

    Solution processing has been recently considered as an option when trying to reduce the costs associated with deposition under vacuum. In this context, most of the research efforts have been centered in the development of the semiconductors processes nevertheless the development of the most suitable dielectrics for oxide based transistors is as relevant as the semiconductor layer itself. In this work we explore the solution combustion synthesis and report on a completely new and green route for the preparation of amorphous aluminum oxide thin films; introducing water as solvent. Optimized dielectric layers were obtained for a water based precursor solution with 0.1 M concentration and demonstrated high capacitance, 625 nF cm(-2) at 10 kHz, and a permittivity of 7.1. These thin films were successfully applied as gate dielectric in solution processed gallium-zinc-tin oxide (GZTO) thin film transistors (TFTs) yielding good electrical performance such as subthreshold slope of about 0.3 V dec(-1) and mobility above 1.3 cm2 V(-1) s(-1). PMID:25354332

  14. Corrosion Behavior of Ultra-fine Grained 1050 Aluminum Alloy Fabricated by ARB Process in a Buffer Borate Solution

    NASA Astrophysics Data System (ADS)

    Fattah-alhosseini, A.; Gashti, S. O.

    2015-09-01

    Accumulative roll bonding (ARB) has been used as a severe plastic deformation process for the industrial production of ultra-fine grained (UFG) and nano-crystalline sheets with excellent mechanical properties. In the present study, the effect of the ARB process on the corrosion behavior of UFG and nano-crystalline 1050 aluminum alloy in a buffer borate solution (pH 5.5) has been investigated. The result of microhardness tests revealed that microhardness values increase with an increasing number of ARB cycles. A sharp increase in microhardness is seen after three ARB cycles, whereas moderate additional increases are observed afterward for up to nine cycles. Also, the XRD results showed that the mean crystallite size decreased to about 91 nm after nine cycles. The potentiodynamic plots show that as a result of ARB, the corrosion behavior of the UFG and nano-crystalline specimens improves, compared to the annealed 1050 aluminum alloy. Moreover, electrochemical impedance spectroscopy measurements showed that the polarization resistance increases with an increasing number of ARB cycles.

  15. Concentration dependence of ionic conductance measured with ion-selective sub-micro pipette probes in aqueous sodium and potassium chloride solutions

    NASA Astrophysics Data System (ADS)

    Son, J. W.; Takami, T.; Lee, J.-K.; Kawai, T.; Park, B. H.

    2011-07-01

    Selective ionic currents in aqueous sodium and potassium chloride solutions with concentrations from 0.01 M to 1.0 M were measured using sub-micro pipette probes in which a poly(vinyl chloride) film containing crown ethers selectively filtered sodium or potassium ions. The selective ionic currents were monitored with a sub-picoampere current measurement system developed from the techniques of TΩ-gap impedance scanning tunneling microscopy. The ionic currents increased with the concentration of the corresponding solution, and thus these sub-micro pipette probes can be applied to detect local ionic concentration of a specific ion in living cells with ionic concentration higher than 0.1 M.

  16. Structure and Stability of Long Rod-like Dodecyltrimethylammonium Chloride Micelles in Solutions of Hydroxybenzoates: A Molecular Dynamics Simulation Study.

    PubMed

    Gujt, Jure; Bešter-Rogač, Marija; Spohr, Eckhard

    2016-08-16

    The relative position of the hydroxylic and carboxylic groups in the isomeric hydroxybenzoate (HB) anions is experimentally known to have a large impact on the thermodynamics of micellization of cationic surfactants, such as dodecyltrimethylammonium chloride (DTAC), and on the structure of the resulting micelles. To understand the effect of the different isomers on the molecular level, we employed atomistic molecular dynamics simulations to study systems containing infinitely long cylindrical DTAC micelles in aqueous solutions of the sodium salts of all three isomers of HB at a temperature and a pressure of 298.15 K and 1 atm. In all studied systems, the number of DTAC unimers is identical to the number of HB anions. At this concentration, the initially cylindrical micelles remain stable, irrespective of the nature of the isomer, whereas micelles rapidly disintegrated in the absence of HB anions. The HB isomers decrease the line density of unimers along the micellar axis and its concomitant thickness in the order o-HB > m-HB > p-HB. It is further observed that o-HB anions penetrate more deeply into the micellar core, induce a more ordered internal structure of the micelle, and are oriented more strongly than the other two isomers. In addition, the ortho isomer shows two different preferential orientations with respect to the radial direction of the cylindrical micelle; it can either be incorporated almost completely into the micelle or it can be attached through hydrogen bonding to one of those o-HB anions that are already incorporated into the micelle, and thus stick out of the micellar surface. PMID:27442259

  17. Universal charge quenching and stability of proteins in 1-methyl-3-alkyl (hexyl/octyl) imidazolium chloride ionic liquid solutions.

    PubMed

    Rawat, Kamla; Bohidar, H B

    2012-09-13

    This study reports pH dependent stability of protein dispersions of five common proteins, bovine serum albumin (BSA), human serum albumin (HSA), immunoglobulin (IgG), β-lactoglobulin (β-Lg), and gelatin-B (Gel-B), all having isoelectric pH, pI ≈ 5, in room temperature ionic liquid solutions of 1-methyl-3-alkyl (hexyl/octyl) imidazolium chloride (concentration 0-0.2% w/v). Molecular hydrophobicity index, (H-index = hydrophobicity/hydrophilicity) of these molecules spanned the range 0.43-0.87. Electrophoretic characteristics, surface tension data and hydrodynamic size information revealed that IL solutions provide dispersion stability owing to specific protein-IL binding which did not alter their pI values though their surface charge was considerably screened. Change in maximum (ζ(max)) and minimum (ζ(min)) zeta potential values observed at pH ~3 (maximum protonated state) and pH ~8 (maximum deprotonated state) could be described universally as function of IL concentration, c as Δζ(x) = [1 - exp(-ac)] where Δζ(x) is either |(ζ(max) - ζ(w))|/ζ(w) or |(ζ(min) - ζ(w))|/ζ(w), and ζ(w) is the corresponding value in water. Tensiometry data showed two major stages of protein-IL interactions: (i) for c < cmc of IL, the IL molecules selectively bind with imidazolium cation through electrostatic forces forming protein-IL (complex) and (ii) for c> cmc free IL-aggregates begin to form. Similarly, we can define Δγ(x) as either |(γ(max) - γ(w))|/γ(w) at pH 3 or |(γ(min) - γ(w))|/γ(w) at pH 8. Both Δζ(x) and Δγ(x) showed linear dependence with c, Δγ(min, max) (or Δζ(min, max)) = (1 - K(γ) (or K(ζ)) H-index), where the slopes K(ζ) and K(γ) defined intermolecular interactions. Hydrodynamic radii data revealed protein stabilization, circular dichroism spectra implied retention of secondary structures, and Raman spectra confirmed a marginal increase in water structure. Results concluded that selective binding of IL molecules to protein surface in

  18. Adsorption of Rh(III) complexes from chloride solutions obtained by leaching chlorinated spent automotive catalysts on ion-exchange resin Diaion WA21J.

    PubMed

    Shen, Shaobo; Pan, Tonglin; Liu, Xinqiang; Yuan, Lei; Wang, Jinchao; Zhang, Yongjian; Guo, Zhanchen

    2010-07-15

    It was found that Rh, Pd and Pt contained in the spent ceramic automotive catalysts could be effectively extracted by dry chlorination with chlorine. In order to concentrate Rh(III) ions contained in the chloride solutions obtained, thermodynamic and kinetics studies for adsorption of Rh(III) complexes from the chloride solutions on an anionic exchange resin Diaion WA21J were carried out. Rh, Pd, Pt, Al, Fe, Si, Zn and Pb from the chloride solution could be adsorbed on the resin. The distribution coefficients (K(d)) of Rh(III) decreased with the increase in initial Rh(III) concentration or in adsorption temperature. The isothermal adsorption of Rh(III) was found to fit Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich models under the adsorption conditions. The maximum monolayer adsorption capacities Q(max) based on Langmuir adsorption isotherms were 6.39, 6.61 and 5.81 mg/g for temperatures 18, 28 and 40 degrees C, respectively. The apparent adsorption energy of Rh was about -7.6 kJ/mol and thus Rh(III) adsorption was a physical type. The experimental data obtained could be better simulated by pseudo-first-order kinetic model and the activation energy obtained was 6.54 J/mol. The adsorption rate of Rh(III) was controlled by intraparticle diffusion in most of time of adsorption process. PMID:20346581

  19. Fractionation of residual Al in natural water treatment from reservoir with poly-aluminum-silicate-chloride (PASiC): effect of OH/Al, Si/Al molar ratios and initial pH.

    PubMed

    Yang, Zhonglian; Gao, Baoyu; Wang, Yan; Zhao, Yaqin; Yue, Qinyan

    2012-01-01

    An aluminum fractionation study was conducted for a surface reservoir water treatment to understand the performance of poly-aluminum-silicate-chloride (PASiC) in terms of the residual Al fractions as a function of initial pH. The coagulation performance expressed as turbidity and organic matter removal was established as supporting data. Some extra data were evaluated in terms of the residual Al ratio of the composite PASiC coagulant. The main residual Al sources were the Al fractions derived from the use of PASiC. The turbidity and organic matter removal ability was optimal at initial pH 6.00-7.00, while the concentrations of various residual Al species and the residual Al ratio of PASiC were minimal at an initial pH range of 7.00-8.00. Under the conditions of OH/Al molar ratio = 2.00 and Si/Al molar ratio = 0.05, PASiC had superior coagulation performance and comparatively low residual Al concentrations. The Al fraction in the composite PASiC coagulant seldom remained under such conditions. Experimental data also indicated that the suspended (filterable) Al fraction was the dominant species, and organic-bound or organo-Al complex Al was considered to be the major species of dissolved Al in water treated by PASiC coagulation. Additionally, the dissolved inorganic monomeric Al species dominated the dissolved monomeric Al fraction. PMID:23534222

  20. Cyclic voltammetry in solutions of aluminum bromide and KBr in aromatic hydrocarbons; II: the behavior of Pb and Sn

    SciTech Connect

    Elam, M.; Gileadi, E.

    1983-03-01

    The electrochemical behavior of dilute solutions of SnBr/sub 2/ and PbBr/sub 2/ in a nonpolar solvent system consisting of solutions of 1.0M Al/sub 2/Br/sub 6/ and 0.80M KBr in ethylbenzene was studied. Cyclic voltammograms show well defined peaks for the deposition and dissolution of the divalent metal. Oxidation to the tetravalent state could not be detected in the available potential region. The diffusion coefficients were 1.1 X 10/sup -6/ cm/sup 2//sec for lead and 2.7 X 10/sup -6/ cm/sup 2//sec for tin. Lead ions inhibit the electrodeposition of aluminum while tin ions seem to have little or no effect. An overpotentia associated with initial nucleation on a platinum electrode is observed for both metals and electrodeposition does not star until /eta/ reaches a value of about 30-40 mV. Formation of a thermodynamically unstable Al/Pb alloy at sufficiently cathodic potentials in solutions containing PbBr/sub 2/ is indicated.

  1. Determination by gas-liquid chromatography of trace amounts of soft polyvinyl chloride plastic additives in aqueous solutions. I. Epoxidized vegetable oils.

    PubMed

    Smistad, G; Waaler, T; Roksvaag, P O

    1989-01-01

    A gas-liquid chromatographic method for the determination of epoxidized vegetable oils (EVO), such as epoxidized soybean oil and epoxidized linseed oil, in aqueous solutions is described. The EVOs are extracted with n-hexane and transesterified to the methyl esters by sodium methoxide in methanol. 3% OV-210 is used as the stationary phase. The weakest standard solution corresponds to 5 micrograms/l (5 ppb) of EVO in an aqueous sample. The reproducibility of a single analysis is 5%. The method is used for the determination of EVO in intravenous fluids stored in flexible polyvinyl chloride bags. PMID:2597333

  2. Coagulation behavior and floc properties of compound bioflocculant-polyaluminum chloride dual-coagulants and polymeric aluminum in low temperature surface water treatment.

    PubMed

    Huang, Xin; Sun, Shenglei; Gao, Baoyu; Yue, Qinyan; Wang, Yan; Li, Qian

    2015-04-01

    This study was intended to compare coagulation behavior and floc properties of two dual-coagulants polyaluminum chloride-compound bioflocculant (PAC-CBF) (PAC dose first) and compound bioflocculant-polyaluminum chloride (CBF-PAC) (CBF dose first) with those of PAC alone in low temperature drinking water treatment. Results showed that dual-coagulants could improve DOC removal efficiency from 30% up to 34%. Moreover, CBF contributed to the increase of floc size and growth rate, especially those of PAC-CBF were almost twice bigger than those of PAC. However, dual-coagulants formed looser and weaker flocs with lower breakage factors in which fractal dimension of PAC-CBF flocs was low which indicates a looser floc structure. The floc recovery ability was in the following order: PAC-CBF>PAC alone>CBF-PAC. The flocculation mechanism of PAC was charge neutralization and enmeshment, meanwhile the negatively charged CBF added absorption and bridging effect. PMID:25872730

  3. Parenteral drug products containing aluminum as an ingredient or a contaminant: Response to Food and Drug Administration notice of intent and request for information. ASCN/A. S. P. E. N. Working Group on Standards for Aluminum Content of Parenteral Nutrition Solutions

    SciTech Connect

    Not Available

    1991-03-01

    Aluminum remains a significant contaminant of total parenteral nutrition (TPN) solutions and may be elevated in bone, urine, and plasma of infants receiving TPN. Aluminum accumulation in tissues of uremic patients and adult TPN patients has been associated with low-turnover bone disease. Furthermore, aluminum has also been linked with encephalopathy and anemia in uremic patients and with hepatic cholestasis in experimental animals. Because of the toxic effects of aluminum, the Food and Drug Administration (FDA) recently published a notice of intent to set an upper limit of 25 micrograms/L for aluminum in large-volume parenterals and to require manufacturers of small-volume parenterals, such as calcium and phosphate salts, to measure aluminum content and note this content on the package label. The ASCN/A.S.P.E.N. Working Group on Standards for Aluminum Content of Parenteral Nutrition Solutions supports these intentions and further urges the FDA to require that cumulative aluminum intake in terms of safe, unsafe, and toxic quantities of aluminum per kilogram be made known to physicians and pharmacists preparing the TPN solutions, to ensure that manufacturers use appropriate control procedures in aluminum measurements, and to employ a standard unit of aluminum measurement.

  4. Solvent distributions, solvent orientations and specific hydration regions around 1-adamantyl chloride and adamantane in aqueous solution

    NASA Astrophysics Data System (ADS)

    Ohisa, Masayuki; Aida, Misako

    2011-07-01

    Ab initio molecular orbital theory and Monte Carlo method with molecular mechanics are used to calculate the hydration numbers and solvent configurations around 1-adamantyl chloride in 324 water molecules. In the highest probability region for distribution of water molecules, a water molecule forms two hydrogen bonds with Cl and the adamantane skeleton; in the second highest probability region, a water molecule is located at the rear side. The CH⋯O interaction in the rear side is enhanced by the Cl substitution. The water orientation in the rear side of 1-adamantyl chloride is different from that around a hydrophobic adamantane molecule.

  5. An empirical equation with tables of smoothed solubilities of methane in water and aqueous sodium chloride solutions up to 25 weight percent, 360 degrees C, and 138 MPa

    USGS Publications Warehouse

    Haas, John L.

    1978-01-01

    The total pressure for the system H2O-CH 4 is given by p(total) = P(H2O,t) + exp10[log x(CH 4) - a - b x(CH4)], where P(H2O,t) is the vapor pressure of H2O liquid at the temperature t (?C) and x(CH 4) is the molal concentration of methane in the solution. The terms a and b are functions of temperature only. Where the total pressure and temperature are known, the concentration of methane, x(CH4), is found by iteration. The concentration of methane in a sodium chloride brine, y(CH4), is estimated using the function log y(CH4) = log x(CH4) - A I, where A is the salting out constant and I is the ionic strength. For sodium chloride solutions, the ionic strength is equal to the molality of the salt. The equations are valid to 360?C, 138 MPa, and 25 weight percent sodium chloride.

  6. Chloride removal from vitrification offgas

    SciTech Connect

    Slaathaug, E.J.

    1995-06-01

    This study identified and investigated techniques of selectively purging chlorides from the low-level waste (LLW) vitrification process with the purge stream acceptable for burial on the Hanford Site. Chlorides will be present in high concentration in several individual feeds to the LLW Vitrification Plant. The chlorides are highly volatile in combustion type melters and are readily absorbed by wet scrubbing of the melter offgas. The Tank Waste Remediation System (TWRS) process flow sheets show that the resulting chloride rich scrub solution is recycled back to the melter. The chlorides must be purged from the recycle loop to prevent the buildup of excessively high chloride concentrations.

  7. CO sub 2 induced inhibition of the localized corrosion of aluminum, Al-0. 5% Cu, and Al-2% Cu in dilute HF solution

    SciTech Connect

    Scully, J.R. . Dept. of Materials Science); Peebles, D.E. )

    1991-01-01

    This study presents work on corrosion of aluminum, Al-.5% Cu, and Al-2% Cu. Electrochemical tests were performed in dilute HF solutions both with and without CO{sub 2} sparging. It is suggested that CO{sub 2} or its reaction products interact with the passive film so that exposure of Cu in the oxide-solution interface is minimized. CO{sub 2} is investigated as a corrosion inhibitor. 4 refs. (JDL)

  8. Treatment of Basic Red 29 dye solution using iron-aluminum electrode pairs by electrocoagulation and electro-Fenton methods.

    PubMed

    Yavuz, Yusuf; Shahbazi, Reza; Koparal, A Savaş; Öğütveren, Ulker Bakır

    2014-01-01

    The aim of this study is the treatment of Basic Red 29 (BR29) dye solution using hybrid iron-aluminum electrodes by electrocoagulation and electro-Fenton methods. The effect of current density, initial pH, supporting electrolyte, H₂O₂, and initial dye concentration on dye removal efficiency was investigated, and the best experimental conditions were obtained. Time-coarse variation of UV-Vis spectra and toxicity and chemical oxygen demand (COD) removal were also examined at the best experimental conditions. Both systems were found very successful for the removal of BR29 dye. The removal efficiency of >95% for BR29 dye solution was reached easily in a short time. At the best experimental conditions, for the initial BR29 concentration of 100 mg/L, >95% BR29 dye and 71.43% COD removal were obtained after 20 and 40 min of electrolysis, respectively. Additionally, toxicity results for electro-Fenton treatment of 100 mg/L BR29 were also very promising. According to the results obtained, although electro-Fenton is more effective, both systems can be used successfully to treat textile wastewater including dyes. PMID:24687790

  9. Effect of micro-alloy elements (Ti, Nb, Al and Ca) on corrosion resistance of 26%Cr-2%Mo stainless steel in chloride solutions

    SciTech Connect

    Kim, H.; Lee, Y.D.

    1999-11-01

    Ferritic stainless steels have higher corrosion and stress corrosion cracking resistance in chloride environments than austenitic stainless steels. The production mat of ferritic stainless steels is lower than austenitic stainless steels. However, the application of highly alloyed ferritic stainless steels is limited due to low toughness and intergranular corrosion attack. Corrosion resistance of 26%Cr-2%Mo ferritic steels was evaluated using polarization test in 20% NaCl solution and the ferric chloride test. In addition, TEM and SEM were employed to analyze the secondary phases around the matrix where pitting corrosion occurred. In ferric chloride test the crevice corrosion resistance of non-stabilized alloy and Ca added alloy was lower than that of stabilized alloy and the crevice corrosion resistance of stabilized alloys was independent of stabilizing element such as Ti and Nb. The pitting corrosion resistance in chloride solution depended on micro-alloying elements as well as the surface treatment such as pickling and polishing. The effect of micro-alloy element and surface treatment on corrosion properties was explained with the aid of SEM observations. Among the polished alloys, the addition of Nb was the most effective for pitting corrosion resistance but the addition of Ti or Ca decreased the corrosion resistance. The pickling increased the corrosion resistance in all alloys except alloy No. 4 (Ti + Nb + Al). Pickling effectively increased corrosion resistance of the alloy containing Ti or Ca, due to removal of pit initiation sites associated with TiN inclusions or unstable phase (i.e., CaS, TiN).

  10. Synthesis of nesquehonite by reaction of gaseous CO2 with Mg chloride solution: its potential role in the sequestration of carbon dioxide.

    PubMed

    Ferrini, Vincenzo; De Vito, Caterina; Mignardi, Silvano

    2009-09-15

    In this paper is reported a novel method to synthesize nesquehonite, MgCO(3) x 3H(2)O, via reaction of a flux of CO(2) with Mg chloride solution at 20+/-2 degrees C. The reaction rate is rapid, with carbonate deposition almost complete in about 10 min. The full characterization of the product of synthesis has been performed to investigate its potential role as a "CO(2)-sequestering medium" and a means of disposing Mg-rich wastewater. We investigated the nesquehonite synthesized using SEM, XRD, FTIR and thermal analysis. The thermodynamic and chemical stability of this low-temperature hydrated carbonate of Mg and its possible transformation products make our method a promising complementary solution to other methods of CO(2) sequestration. Carbonation via magnesium chloride aqueous solutions at standard conditions represents a simple and permanent method of trapping CO(2). It could be applied at point sources of CO(2) emission and could involve rejected brine from desalination plants and other saline aqueous wastes (i.e., "produced water"). The likelihood of using the resulting nesquehonite and the by-products of the process in a large number of applications makes our method an even more attractive solution. PMID:19303209

  11. A Solution NMR Investigation into the Early Events of Amelogenin Nanosphere Self-Assembly Initiated with Sodium Chloride or Calcium Chloride

    SciTech Connect

    Buchko, Garry W.; Tarasevich, Barbara J.; Bekhazi, Jacky G.; Snead, Malcolm L.; Shaw, Wendy J.

    2008-12-08

    Using solution-state NMR spectroscopy, new insights into the early intermolecular interactions stabilizing amelogenin supramolecular assembly and the potential role of calcium ions have been discovered. Two-dimensional 1H-15N spectra were recorded for 15N-labeled amelogenin as a function of increasing Ca2+ concentration starting from monomeric conditions. Evidence for protein-protein interactions were observed between residues E18 and E40 in the N-terminus. At higher Ca2+ concentrations there was concurrent involvement of residues in both the N- (Y12-Q56) and the C-terminus (Q144-T171). Neither specific residues nor their stepwise interaction have previously been identified in the initial stages of nanosphere assembly.

  12. Silicon nitride-aluminum oxide solid solution (SiAION) formation and densification by pressure sintering

    NASA Technical Reports Server (NTRS)

    Yeh, H. C.; Sanders, W. A.; Fiyalko, J. L.

    1975-01-01

    Stirred-ball-mill-blended Si3N4 and Al2O3 powders were pressure sintered in order to investigate the mechanism of solid solution formation and densification in the Si3N4-Al2O3 system. Powder blends with Si3N4:Al2O3 mole ratios of 4:1, 3:2, and 2:3 were pressure sintered at 27.6-MN/sq m pressure at temperatures to 17000 C (3090 F). The compaction behavior of the powder blends during pressure sintering was determined by observing the density of the powder compact as a function of temperature and time starting from room temperature. This information, combined with the results of X-ray diffraction and metallographic analyses regarding solutioning and phase transformation phenomena in the Si3N4-Al2O3 system, was used to describe the densification behavior.

  13. Reactive solute transport in an acidic stream: Experimental pH increase and simulation of controls on pH, aluminum, and iron

    USGS Publications Warehouse

    Broshears, R.E.; Runkel, R.L.; Kimball, B.A.; McKnight, Diane M.; Bencala, K.E.

    1996-01-01

    Solute transport simulations quantitatively constrained hydrologic and geochemical hypotheses about field observations of a pH modification in an acid mine drainage stream. Carbonate chemistry, the formation of solid phases, and buffering interactions with the stream bed were important factors in explaining the behavior of pH, aluminum, and iron. The precipitation of microcrystalline gibbsite accounted for the behavior of aluminum; precipitation of Fe(OH)3 explained the general pattern of iron solubility. The dynamic experiment revealed limitations on assumptions that reactions were controlled only by equilibrium chemistry. Temporal variation in relative rates of photoreduction and oxidation influenced iron behavior. Kinetic limitations on ferrous iron oxidation and hydrous oxide precipitation and the effects of these limitations on field filtration were evident. Kinetic restraints also characterized interaction between the water column and the stream bed, including sorption and desorption of protons from iron oxides at the sediment-water interface and post-injection dissolution of the precipitated aluminum solid phase.

  14. Sorption of Ponceau 4R anionic dye from aqueous solutions on aluminum oxide and polyurethane foam

    NASA Astrophysics Data System (ADS)

    Tikhomirova, T. I.; Ramazanova, G. R.; Apyari, V. V.

    2014-12-01

    The sorption of Ponceau 4R (E-124) anionic dye on polyurethane foam based on ethers and γ-Al2O3 from aqueous solutions is studied. It is established that sorption is highest in the range of 0.5 M HCl, pH 2 on polyurethane foam and 0.2 M HCl, pH 6.5 on γ-Al2O3. Under optimum conditions, the degrees of recovery on polyurethane foam and γ-Al2O3 are 20-30 and 70-85%, respectively. A possible scheme of interactions between the dye and the surfaces of sorbents is proposed.

  15. Effect of varying nonwoven cotton substrate and the properties of the surfactant solution upon the adsorption of aqueous solutions of alkyl-dimethyl-benzyl-ammonium chloride

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The adsorption of alkyl-dimethyl-benzyl-ammonium chloride (ADBAC), a cationic surfactant commonly employed as an antimicrobial agent, on greige, alkaline scoured, and bleached nonwoven cotton fabrics was investigated at varying surfactant concentrations using UV/vis spectroscopy. Results show greige...

  16. Effect of varying nonwoven cotton substrate and the properties of the surfactant solution upon the adsorption of aqueous solutions of alkyl-dimethyl-benzyl-ammonium chloride

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The adsorption of alkyl-dimethyl-benzyl-ammonium chloride (ADBAC), a cationic surfactant commonly employed as an antimicrobial agent, on greige, alkaline scoured, and bleached nonwoven cotton fabrics was investigated at varying surfactant concentrations and liquor ratios using UV-vis absorption spec...

  17. Comparative characteristics of MA-40 and MA-41 membranes under conditions of maximal concentration of sodium chloride solutions by electrodialysis

    SciTech Connect

    Grebenyok, V.D.; Lokota-Fabulyak, Y.G.; Ponomareu, M.I.

    1985-10-01

    This paper gives a quantitative assessment of salt diffusion from brine into the diluate, and osmotic and electro-osmotic transport of water into the brine compartments in concentration of sodium chloride with the use of commercially produced ion-exchange membranes MK-40, MA-40, and MA-41. A schematic diagram of the electrochemical cell, comprising electrode compartments, desalination compartments, and concentrating compartments is presented. It is shown that although brines of higher concentration can be obtained by the use of MA-41 membranes, it is economically preferable to use MA-40 membranes for concentrating sodium chloride. The higher electrical conductivity of MA-40 in comparison with MA-41 lowers the energy consumption for brine production in the former.

  18. Generation of sodium hypochlorite (NaOCl) from sodium chloride solution using C/PbO2 and Pb/PbO2 electrodes

    NASA Astrophysics Data System (ADS)

    Ghalwa, Nasser Abu; Tamos, Hassan; ElAskalni, Mohamed; El Agha, Abed Rhman

    2012-06-01

    Two modified electrodes (Pb/PbO2 and C/PbO2) were prepared by electrodepositing a lead oxide layer on lead and carbon substrates. These modified electrodes were used as anodes for the generation of sodium hypochlorite (NaOCl) from sodium chloride solution. Different operating conditions and factors affecting the treatment process of NaOCl generation, including current density, pH values, conductive electrolytes, and electrolysis time, were studied and optimized. By comparison the C/PbO2 electrode shows a higher efficiency than the Pb/PbO2 electrode for the generation of NaOCl.

  19. [Assay of three kinds of aluminum fractions (Al(a), Al(b) and Al(c)) in polynuclear aluminum solutions by Al-Ferron timed spectrophotometry and demarcation of their time limits].

    PubMed

    Wang, Chen-yi; Zhang, Cai-hua; Bi, Shu-ping; Zhang, Zhen-chao; Yang, Wei-hua

    2005-02-01

    Al-Ferron timed spectrophotometry assay is a basic method in the study on the formation of polynuclear hydroxyl aluminum species and their transformation laws in aqueous systems. In actual working process, this methodology has some dogmatism and arbitrariness in the time limits demarcation of the three kinds of aluminum fractions (Al(a), Al(b) and Al(c)) in polynuclear aluminum solutions, which makes this kind of classification rougher, and the experimental results non-reproducible. The reason for this difference is that the specific species within Al(a), Al(b) and Al(c) have different reaction mechanism and dynamics, and that specific species of Al(b) having different OH/Al ratios have different reaction rates with ferron. In this paper, the ExpAssoc distribution was applied to quantitatively fit the Al-Ferron reaction dynamics curve, and the extrapolation method was used to survey the 1 min measured value [Al(a)] of monomeric Al, which is hard to obtain in manual manipulation. The time demarcation between Al(b) and Al(c) should reach the point of the experimental data curve up to horizontal platform. The microwave-radiated technology was used to fast assay the total aluminum concentration [Al(T)]. With these methods, the contents of monomeric Al(a), polynuclear Al(b) and gel Al(c) can be conveniently and quantitatively measured. It offers a novel method for surmounting the arbitrariness in the measurement of the three kinds of aluminum fractions and the repetitive calculation of Al(a) and Al(b). PMID:15852869

  20. The development of BCB-sealed galvanic cells. Case study: aluminum-platinum cells activated with sodium hypochlorite electrolyte solution

    NASA Astrophysics Data System (ADS)

    Dlutowski, J.; Biver, C. J.; Wang, W.; Knighton, S.; Bumgarner, J.; Langebrake, L.; Moreno, W.; Cardenas-Valencia, A. M.

    2007-08-01

    Energy on demand is an important concept in remote sensor development. The fabrication process for silicon-wafer-based, totally enclosed galvanic cells is presented herein. Benzocyclyobutene (BCB), a photo-patternable material, is used as the adhesive layer between the silicon wafers on which metal electrodes are patterned to form the cells' electrolyte cavity. As a case study, and since aluminum is an anode material with thermodynamic high energy density, this metal is evaporated onto a wafer and used as an anode. A sputtered platinum film collects the charge and provides a catalytic surface in the cell cathode. The metal film patterning process and wafer-to-wafer bonding with BCB is detailed. The difficulties encountered, and design modifications to overcome these, are presented. Cells of the mentioned design were activated with sodium hypochlorite solution electrolyte. Typical potential outputs for the cells, as a function of operational time, are also presented. With a 5 kΩ load, a potential of 1.4 V was maintained for over 240 min, until depletion of the electrolyte occurred. Average cell energy outputs under electrical loads between 100 Ω and 5 kΩ were in the range of 4-10 J with columbic densities ranging from 45 to 83 Ah L-1.

  1. Reaction of. cap alpha. ,. cap alpha. ,omega-trihydroperfluoroalkanols with thionyl chloride

    SciTech Connect

    Krolevets, A.A.; Ragulin, L.I.; Popov, A.G.

    1987-06-10

    The effect of catalysts on the reaction of thionyl chloride with ..cap alpha..,..cap alpha..,omega-trihydroperfluoroalkanols was investigated. It was shown that the use of calcium chloride, aluminum chloride, ferric chloride, and magnesium chloride as catalysts makes it possible to obtain polyfluoroalkyl chlorosulfites and bis(polyfluoroalkyl) sulfites with good yields.

  2. ALUMINUM RECLAMATION BY ACIDIC EXTRACTION OF ALUMINUM-ANODIZING SLUDGES

    EPA Science Inventory

    Extraction of aluminum-anodizing sludges with sulfuric acid was examined to determine the potential for production of commercial-strength solutions of aluminum sulfate, that is liquid alum. The research established kinetic and stoichiometric relationships and evaluates product qu...

  3. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... GRAS § 184.1138 Ammonium chloride. (a) Ammonium chloride (NH4Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  4. The inhibitive mechanisms of nitrite and molybdate anions on initiation and propagation of pitting corrosion for mild steel in chloride solution

    NASA Astrophysics Data System (ADS)

    Zhou, Yong; Zuo, Yu

    2015-10-01

    The inhibitive mechanism of NO2- and MoO42- on the initiation and propagation of pitting corrosion for mild steel in chloride solution was studied with electrochemical methods and X-ray photoelectron spectroscopy (XPS). In 0.1 M NaCl solution both the addition of 0.2 M NaNO2 and 0.2 M Na2MoO4 effectively promoted passivation of mild steel. The passive film on the steel surface formed in NaCl + NO2- solution was composed of mainly γ-Fe2O3, and the film formed in NaCl + MoO42- solution was composed of two components: one is Fe2(MoO4)3 and the other is an oxide composed of Fe and O. The film formed in NaNO2 solution has lower oxygen vacancies and larger impedance than the film formed in Na2MoO4 solution. NO2- shows better inhibition to the initiation of pitting corrosion than MoO42-, which is attributed to its strong oxidability that results in the formation of a stable γ-Fe2O3 film. However, in NaNO2 solution, once a pit forms, it is more difficult to get repassivated than the situation in Na2MoO4 solution. The main reason is due to that in a propagating pit MoO42- anions result in increased solution pH value, but conversely NO2- anions lead to a decreased solution pH value within a pit.

  5. Behavior of thermal spray aluminum coating in wet H{sub 2}S environments

    SciTech Connect

    Joia, C.; Berrera, P.; Kane, R.D.

    1999-11-01

    Sulfide stress cracking (SSC) and hydrogen induced cracking can cause severe damage in steel equipment exposed to wet H{sub 2}S environments. Metallic thermal spray coatings based on aluminum protect carbon steel from the corrosive media, when wet H{sub 2}S environments are a concern. In this program, a series of electrochemical tests were conducted. These tests involved exposure of coated samples to various environments containing H{sub 2}S, ammonia, chloride and cyanide to study the behavior of the aluminum coating associated with a stainless steel interlayer both applied by thermal spray. Results showed that the aluminum layer was corroded rapidly in solutions with pH higher than 11. In alkaline solutions with pH lower than 9 a protective aluminum layer and the corrosion rate was very low.

  6. VOLATILE CHLORIDE PROCESS FOR THE RECOVERY OF METAL VALUES

    DOEpatents

    Hanley, W.R.

    1959-01-01

    A process is presented for recovering uranium, iron, and aluminum from centain shale type ores which contain uranium in minute quantities. The ore is heated wiih a chlorinating agent. such as chlorine, to form a volatilized stream of metal chlorides. The chloride stream is then passed through granular alumina which preferentially absorbs the volatile uranium chloride and from which the uranium may later be recovered. The remaining volatilized chlorides, chiefly those of iron and aluminum, are further treated to recover chlorine gas for recycle, and to recover ferric oxide and aluminum oxide as valuable by-products.

  7. Electrical characterizations of smart hydrogel based on chitosan/poly(diallydimethylammonium chloride) in NaCl solutions

    NASA Astrophysics Data System (ADS)

    Yoon, Seoung Gil; Park, Sang Jun; Lim, Jun Young; Kim, Min Sup; Cho, Baek Hwan; Lee, Sang Min; Kim, Seon Jeong

    2004-07-01

    Temperature- and pH-responsive semi-interpenetrating polymer network (SIPN) hydrogels, constructed with chitosan (CS) and poly(diallyldimethylammonium chloride) (PDADMAC), were studied. The characterizations of the IPN hydrogels were investigated by swelling tests and bending experiments, under various conditions. When the swollen IPN hydrogel was placed between a pair of electrodes it exhibited bending behavior on the application of an electric field, which showed stepwise bending behavior depending on the magnitude of the electrical stimulus. In order to clarify the relationship between the equilibrium swelling ratio and bending behavior of the SIPN hydrogels, the state of water in the SIPN hydrogel was also investigated using differential scanning calorimetry (DSC).

  8. Production of concentrated caustic soda and hydrochloride acid solutions from sodium chloride by electrodialysis with the aid of bipolar ion-exchange membranes

    SciTech Connect

    Greben', V.P.; Pivovarov, N.Ya.; Latskov, V.L.

    1988-10-20

    This paper gives a comparative analysis of the action of electrodialyzers containing three and five compartments in the structural unit, and equipped with bipolar, cation-exchange, and anion-exchange membranes, used for production of hydrochloric acid and caustic soda from sodium chloride solutions. It was shown that an electrodialyzer with five compartments gives hydrochloric acid and caustic soda for 2.5-3 M concentration with 0.2-0.3 current efficiency, whereas an electrodialyzer with three compartments in the structural unit gives hydrochloric acid and caustic soda concentrations of about 1.2 M at the same current efficiency. The performance of the electrodialyzers was analyzed and equations were derived for calculating the current efficiencies for acid and alkali under conditions of acidification of the salt solution; this was based on determination of the transport numbers of ions passing through the membranes.

  9. Effect of OH-/Al3+ and Si/Al molar ratios on the coagulation performance and residual Al speciation during surface water treatment with poly-aluminum-silicate-chloride (PASiC).

    PubMed

    Yang, Zhonglian; Gao, Baoyu; Xu, Weiying; Cao, Baichuan; Yue, Qinyan

    2011-05-15

    Coagulation performance, mechanism of poly-aluminum-silicate-chloride (PASiC) and residual Al speciation in the effluent with respect to a specific surface water treatment in China were comprehensively investigated in this study. The impact of OH(-)/Al(3+) and Si/Al molar ratios on the coagulation performance, mechanism and residual Al speciation of PASiC in surface water treatment was discussed as a function of coagulant dosage. It was intended to provide an insight into the relationship between coagulation performance and residual Al. Experimental results revealed that when OH(-)/Al(3+) molar ratio = 2.00 and Si/Al molar ratio = 0.0500 in PASiC coagulant, PASiC exhibited beneficial coagulation property and relatively lower content of residual Al. Surface bridging and entrapment was more effective compared with charge neutralization during the specific surface water treatment. The majority of residual Al in the effluent existed in the form of insoluble suspended or particulate Al. Dissolved organically bound Al was almost the major speciation in dissolved Al and dissolved inorganically bound monomeric Al was the only component in dissolved monomeric Al. Al in PASiC remained abundant at lower dosages and residual Al concentration could be effectively reduced at the dosages of 12.0-15.0mg/L as Al. PMID:21376461

  10. PROCESS FOR REMOVING ALUMINUM COATINGS

    DOEpatents

    Flox, J.

    1959-07-01

    A process is presented for removing aluminum jackets or cans from uranium slugs. This is accomplished by immersing the aluminum coated uranium slugs in an aqueous solution of 9 to 20% sodium hydroxide and 35 to 12% sodium nitrate to selectively dissolve the aluminum coating, the amount of solution being such as to obtain a molar ratio of sodium hydroxide to aluminum of at least

  11. Corrosion protection of untreated AA-2024-T3 in chloride solution by a chromate conversion coating monitored with Raman spectroscopy

    SciTech Connect

    Zhao, J.; Frankel, G.; McCreery, R.L.

    1998-07-01

    The behavior of chromate conversion coatings (CCCs) on the aluminum aircraft alloy AA 2024-T3 was examined by several types of experiments, using Raman spectroscopy as a primary technique. First, Raman spectra of the CCC film made from a commercial process revealed a Raman feature characteristic of Cr(VI) which was distinct from Raman bands to an initially untreated alloy sample. The release of chromate from a CCC was demonstrated, as was redeposition of a chromate film on the fresh alloy surface. Formation of a Raman-observable Cr(VI)-containing deposit was more rapid in or near pits in the untreated alloy sample, and the deposit was spectroscopically very similar to the original CCC film. The initially untreated alloy became much less active toward corrosion after migration of chromate from the nearby CCC film, with the polarization resistance increasing by at least two orders of magnitude and the pitting potential increasing by 60 mV. The results clarify the mechanism of self-healing exhibited by CCC films, in which chromate species released from the CCC migrate to an actively corroding region and stop aluminum dissolution. The migrating chromate is selectively deposited at active corrosion sites, either by forming an insoluble Al/chromate precipitate or by adsorption by previously formed corrosion products.

  12. Extractive separation of sodium 22 and aluminum 26 from cyclotron-irradiated magnesium targets

    SciTech Connect

    Iofa, B.Z.; Dzhigirkhanov, M.S.A.; Maklachkov, A.G.; Ovcharenko, V.P.; Sevast'yanov, Yu.G.; Silant'ev, A.I.

    1988-05-01

    An extraction procedure has been developed for the successive isolation of carrier-free sodium 22 and aluminum 26 from deuteron- (proton-) irradiated magnesium targets. The irradiated magnesium metal or alloy target is dissolved in sulfuric acid and the pH adjusted to 1.0-1.5 with ammonia. Sodium 22 is extracted with a chloroform solution of 15-crown-5 and picric acid and back-extracted with water in the presence of tetraphenylphosphonium chloride or a tetraalkylammonium chloride. Then aluminum 26 is extracted by trioctyl-ammonium oxalate in benzene (toluene) containing chloroform and back-extracted with 6M hydrochloric acid. The yields of sodium 22 and aluminum 26 are better than 95%.

  13. Energetic Insight into the Formation of Solids from Aluminum Polyoxocations.

    PubMed

    Reusser, Dana; Casey, William H; Navrotsky, Alexandra

    2015-08-01

    The ε-Keggin [AlO4Al12(OH)24(H2O)12](7+) ion (AlAl12(7+)) is a metastable precursor in the formation of aluminum oxyhydroxide solids. It also serves as a useful model for the chemistry of aluminous mineral surfaces. Herein we calculate the enthalpies of formation for this aqueous ion and its heterometal-substituted forms, GaAl12(7+) and GeAl12(8+), using solution calorimetry. Rather than measuring the enthalpies of the MAl12(7/8+) ions directly from solution hydrolysis, we measured the metathesis reaction of the crystallized forms with barium chloride creating an aqueous aluminum solution monospecific in MAl12(7/8+). Then, the contributions to the heat of formation from the crystallized forms were subtracted using referenced states. When comparing the aqueous AlAl12(7+) ion to solid aluminum (oxy)-hydroxide phases, we found that this ion lies closer in energy to solid phases than to aqueous aluminum monomers, thus explaining its role as a precursor to amorphous aluminum hydroxide phases. PMID:26129924

  14. [Inhibition of growth of E. coli cells by anolites of sodium and potassium chloride after processing solutions in a diaphragmatic electrolyzer].

    PubMed

    Miroshnikov, A I

    1998-01-01

    The relationship between the inhibitory effect of sodium chloride and potassium anolites, obtained in a diaphragm electrolyser, and the physicochemical parameters of solutions was compared with that between the inhibitory effect and physicochemical properties of hypochlorites obtained after treating the solutions in an electrolyser having no diaphragm was compared. The biological activity of solutions containing molecular chlorine, hypochlorous acid, and hypochlorite ions was determined by their effect on the growth of E. coli cells. After a 5-min incubation of cells with each of the oxidizers, the bacterial growth stopped and was not restored during one day. The conclusion is made that the oxidizers irreversibly disturb the barrier properties of cell membranes and, in some cases, destroy cells. In model solutions, as well as in solutions treated after heating on a water bath or after the addition of sodium thiosulfate, a delay in the start of E. coli growth occurs. After the lag-phase, the repair of cells sets on, and after a day the optical density of cells increases and approaches the control. PMID:10079921

  15. Long-term cement corrosion in chloride-rich solutions relevant to radioactive waste disposal in rock salt - Leaching experiments and thermodynamic simulations

    NASA Astrophysics Data System (ADS)

    Bube, C.; Metz, V.; Bohnert, E.; Garbev, K.; Schild, D.; Kienzler, B.

    Low- and intermediate-level radioactive wastes are frequently solidified in a cement matrix. In a potential repository for nuclear wastes, the cementitious matrix is altered upon contact with solution and the resulting secondary phases may provide for significant retention of the radionuclides incorporated in the wastes. In order to assess the secondary phases formed upon corrosion in chloride-rich solutions, which are relevant for nuclear waste disposal in rock salt, leaching experiments were performed. Conventional laboratory batch experiments using powdered hardened cement paste in MgCl2-rich solutions were left to equilibrate for up to three years and full-scale cemented waste products were exposed to NaCl-rich and MgCl2-rich solutions for more than twenty years, respectively. Solid phase analyses revealed that corrosion of hardened cement in MgCl2-rich solutions advanced faster than in NaCl-rich solutions due to the extensive exchange of Mg from solution against Ca from the cementitious solid. Thermodynamic equilibrium simulations compared well to results at the final stages of the respective experiments indicating that close to equilibrium conditions were reached. At high cement product to brine ratios (>0.65 g mL-1), the solution composition in the laboratory-scale experiments was close to that of the full-scale experiments (cement to brine ratio of 2.5 g mL-1) in the MgCl2 systems. The present study demonstrates the applicability of thermodynamic methods used in this approach to adequately describe full-scale long-term experiments with cemented waste simulates.

  16. Spectroscopic determination of hypochlorous acid, in chloride brine solutions, featuring 5 MeV proton beam line experiments

    NASA Astrophysics Data System (ADS)

    Hartmann, Thomas; Paviet-Hartmann, Patricia; Wetteland, Christopher; Lu, Ningping

    2003-04-01

    The irradiation effects of 4.9 MeV protons on salt repository related brines are investigated spectrophotometrically. The induced formation of hypochlorous acid is determined up to doses of 11 kGy in 3.7 M MgCl 2·6H 2O and in a multicomponent brine of high concentration: Brine G. The build-up of hypochlorous acid to a steady-state concentration is found to be independent on the chloride concentration. The ultimate objective of this experiment is the estimation of the G value for HOCl in which meaningful predictions of long-term redox conditions in a nuclear repository strongly depend on. This paper describes our first steps towards the determination of HOCl.

  17. Cation sorption on the muscovite (0 0 1) surface in chloride solutions using high-resolution X-ray reflectivity

    NASA Astrophysics Data System (ADS)

    Schlegel, Michel L.; Nagy, Kathryn. L.; Fenter, Paul; Cheng, Likwan; Sturchio, Neil C.; Jacobsen, Steven D.

    2006-07-01

    The structure and mechanism of cation sorption at the (0 0 1) muscovite-water interface were investigated in 0.01 and 0.5 m KCl, CsCl, and CaCl 2 and 0.01 m BaCl 2 solutions at slightly acidic pH by high-resolution X-ray reflectivity. Structural relaxations of atom positions in the 2 M1 muscovite were small (⩽0.07 Å) and occurred over a distance of 30 to 40 Å perpendicular to the interface. Cations in all solutions were sorbed dominantly in the first and second solution layers adjacent to the mineral surface. The derived heights of the first solution layer in KCl and CsCl solutions, 1.67(6)-1.77(7) and 2.15(9)-2.16(2) Å, respectively, differ in magnitude by the approximate difference in crystallographic radii between K and Cs, and correspond closely to the interlayer cation positions in bulk K- and Cs-mica structures. The first solution layer heights in CaCl 2 and BaCl 2 solutions, 2.46(5)-2.56(11) and 2.02(5) Å, respectively, differ in a sense opposite to that expected based on crystallographic or hydrated radii of the divalent cations. The derived ion heights in all solutions imply that there is no intercalated water layer between the first solution layer and the muscovite surface. Molecular compositions were assigned to the first two solution layers in the electron density profiles using models that constrain the number density of sorbed cations, water molecules, and anions by considering the permanent negative charge of the muscovite and average solution density. The models result in partial charge balance (at least 50%) by cations sorbed in the first two layers in the 0.01 m solutions and approximately full charge balance in the 0.5 m solutions. Damped oscillations of model water density away from the first two solution layers agree with previous X-ray reflectivity results on the muscovite (0 0 1) surface in pure water.

  18. Molecular structure and dynamics of an aqueous sodium chloride solution in nano-pores between portlandite surfaces: a molecular dynamics study.

    PubMed

    Dongshuai, Hou; Zeyu, Lu; Peng, Zhang; Qingjun, Ding

    2016-01-21

    Portlandite plays an important role in the hydration phase of cement-based materials and influences the strength and durability of such materials. This study describes a molecular dynamics study of the structure and dynamics of water and ions confined at ambient temperature in calcium hydroxyl nanopores with widths of 35 Å. Strong layering of water in the vicinity of the (001) surface of portlandite demonstrates special structural features such as large density, good orientation preference, ordered interfacial organization and low diffusion rate. Due to the fixed vibration and rotation of the hydroxyl groups at the interface, water molecules within the first adsorbed layer adopt both H-downward and H-upward orientations by donating H-bonds and accepting H-bonds from the OH groups in the solid surface. Regarding the interaction of the ions and portlandite, Na(+) ions, deeply rooted in spaces in the surface hydroxyl groups, are significantly slowed and remain near the surface for long periods of time. On the other hand, due to the weak H-bonds formed by chloride ions and hydroxyl groups, adsorbed chloride ions near the surface cannot remain for longer times. In addition, when water and ions are confined in the nano-pores, the residence time for the ion-water and ion-ion clusters is lengthened so that the ion adsorption capability of the porlandite surface is enhanced due to the stable Na-Cl connections in the electrolyte solution. PMID:26687688

  19. Chloride Test

    MedlinePlus

    ... Addison disease, or increased salt intake. If both chloride and sodium levels are high in a person on a ... anything else I should know? Drugs that affect sodium blood levels will also cause changes in chloride. In addition, swallowing large amounts of baking soda ...

  20. The solubility of quartz in aqueous sodium chloride solution at 350°C and 180 to 500 bars

    USGS Publications Warehouse

    Fournier, Robert O.; Rosenbauer, Robert J.; Bischoff, James L.

    1982-01-01

    The solubility of quartz in 2, 3, and 4 molal NaCl was measured at 350°C and pressures ranging from 180 to 500 bars. The molal solubility in each of the salt solutions is greater than that in pure water throughout the measured pressure range, with the ratio of solubility in NaCl solution to solubility in pure water decreasing as pressure is increased. The measured solubilities are significantly higher than solubilities calculated using a simple model in which the water activity in NaCl solutions decreases either in proportion to decreasing vapor pressure of the solution as salinity is increased or in proportion to decreasing mole fraction of water in the solvent.

  1. Solubility of lead as lead (II) chloride in HEPES-Ringer and artificial seawater (Ca-ASW) solutions.

    PubMed

    Matthews, M R; Parsons, P J; Carpenter, D O

    1993-01-01

    Total dissolved Pb was measured in a number of commonly used physiological solutions by electrothermal atomization atomic absorption spectrometry (ETA-AAS). In HEPES-buffered solutions (pH 7.30) the concentration of total Pb in solution ("measured" Pb) was only 77% of nominal Pb up to 20 microM added Pb, where experiments were undertaken at room temperature (22 +/- 1 degree C). However, test solutions equilibrated at 37 +/- 1 degree C contained 99% of added Pb up to 2 microM. Above this nominal concentration, percentage recoveries dropped to approximately 72% at a nominal concentration of 20 microM. Tris-buffered artificial seawater (CaASW) solutions (pH 7.60) contained more dissolved Pb compared to HEPES-buffered solutions at 22 degrees C. However, increasing the calcium concentration in ASW appeared to increase precipitation of PbCl2. Concentration-corrected dose-response relationships were plotted from previously published data on the effects of Pb on voltage-activated calcium channels of rat dorsal root ganglion (DRG) cells and Aplysia neurons. The plots suggest that the inhibitory effects of Pb on rat DRG cells may prevail at concentrations of Pb even lower than reported previously when measurements were made at 22 degrees C. However, increasing the temperature to 37 degrees C resulted in closer agreement between measured and nominal dose-response curves. The measured dose-response curves for the Tris-buffered ASW solutions closely followed those of the nominal up to 200 microM Pb. In ASW solutions containing 40 mM calcium, PbCl2 was precipitated at Pb concentrations greater than 200 microM. PMID:8247402

  2. Laboratory studies of the low-temperature deliquescence of calcium chloride salts: Relevance to aqueous solutions on Mars and in the Antarctic Dry Valleys

    NASA Astrophysics Data System (ADS)

    Gough, R. V.; Chevrier, V.; Tolbert, M. A.

    2013-12-01

    There is significant interest in the possible existence of liquid water on current Mars. This water would likely exist as a brine in order to be stable on Mars today. It has been proposed that soil salts could form aqueous solutions through either the melting of ice by low-eutectic salts, or by the deliquescence of hygroscopic salts present in the Martian soil. The focus thus far has largely been on perchlorate species, which can melt ice at temperatures as low as 206 K and can deliquesce at relative humidity values as low as 38% RH. A Mars-relevant salt that has been neglected thus far is calcium chloride (CaCl2). Calcium has been reported to be an abundant cation at the Phoenix landing site and Mars Science Laboratory instruments have recently identified calcium as well. Simulations suggest subsurface CaCl2 is an ideal candidate to produce brines with seasonality consistent with observed recurring slope lineae (RSL) (Chevrier et al., 2012). Finally, the only terrestrial site where RSL-like features have been observed (near Don Juan Pond in the Antarctic Dry Valleys) contains abundant CaCl2. These seasonal slope streaks are thought to form when CaCl2 in the soil deliquesces due to contact with atmospheric water vapor (Dickson et al., 2013). It is important to understand how this CaCl2 interacts with water vapor at low temperatures relevant to Mars and the Martian analog sites. Here we use a Raman microscope and environmental cell to monitor the low-temperature (223 - 273 K) deliquescence (solid to aqueous phase transition) and efflorescence (aqueous to solid phase transition) of three hydration states of CaCl2 (dihydrate, tetrahydrate, hexahydrate). We have found that the deliquescence relative humidity (DRH) increases with increasing hydration state, which is an expected result. Average DRH values over the temperature range studied are 20.0 × 2.6% RH for the dihydrate, 31.8 × 6.3% RH for the tetrahydrate and 60.7 × 1.6% RH for the hexahydrate. Once the aqueous

  3. Comparison of the release behaviors of di (2-ethylhexyl) phthalate and tri(2-ethylhexyl) trimellitate from the polyvinyl-chloride infusion set into pharmaceutical solutions.

    PubMed

    Zhang, Hong; Yang, Fengmin; Shen, Gang; Yang, Yueyang; Tang, Yalin

    2015-05-01

    Polyvinyl-chloride (PVC) with plasticizers of di(2-ethylhexyl) phthalate (DEHP) and tris(2-ethyl- hexyl) trimellitate (TOTM) is widely used in medical and paramedical appliances. However, such plasticizers can leach from PVC products into contact solutions. The aim of this study is to investigate the release behaviors of DEHP and TOTM from the PVC intravenous infusion set into various pharmaceutical solutions under the simulated clinical conditions, such as the lipophilic substances (paclitaxel) , parenteral nutrition (fat emulsion injection) , acid and alkali pharmaceutical solution (levofloxacin hydrochloride injection, pH 3.0-5.0 and furosemide, pH 8.0-9.0). A simple and rapid high-performance liquid chromatographic method with UV detection (HPLC-UV) for the determination of DEHP or TOTM released from PVC medical devices into the above intravenous preparations was developed. The cumulative amounts of DEHP or TOTM released in 24 h were in the same following order: paclitaxel > fat emulsion injection levofloxacin hydrochloride > furosemide solution. From a comparison of the cumulative amounts of released DEHP and TOTM from the above solutions, we found that the cumulative amount of TOTM is far less than that of DEHP, under the same conditions. The cumulative amount of the DEHP released in 24 h in the paclitaxel solution was 21. 14 mg, while under the same conditions, the cumulative amount of TOTM was only 0. 078 mg. The cumulative amount of DEHP is assumed to be about 270 times that of the released TOTM. Thus TOTM could be a superior alternative to DEHP for use in medical devices because of its potential lower leachability. PMID:26387211

  4. Electrical Transport and Grain Growth in Solution-Cast, Chloride-Terminated Cadmium Selenide Nanocrystal Thin Films

    PubMed Central

    2015-01-01

    We report the evolution of electrical transport and grain size during the sintering of thin films spin-cast from soluble phosphine and amine-bound, chloride-terminated cadmium selenide nanocrystals. Sintering of the nanocrystals occurs in three distinct stages as the annealing temperature is increased: (1) reversible desorption of the organic ligands (≤150 °C), (2) irreversible particle fusion (200–300 °C), and (3) ripening of the grains to >5 nm domains (>200 °C). Grain growth occurs at 200 °C in films with 8 atom % Cl–, while films with 3 atom % Cl– resist growth until 300 °C. Fused nanocrystalline thin films (grain size = 4.5–5.5 nm) on thermally grown silicon dioxide gate dielectrics produce field-effect transistors with electron mobilities as high as 25 cm2/(Vs) and on/off ratios of 105 with less than 0.5 V hysteresis in threshold voltage without the addition of indium. PMID:24960255

  5. Hydrazino-methoxy-1,3,5-triazine Derivatives' Excellent Corrosion Organic Inhibitors of Steel in Acidic Chloride Solution.

    PubMed

    El-Faham, Ayman; Osman, Sameh M; Al-Lohedan, Hamad A; El-Mahdy, Gamal A

    2016-01-01

    The corrosion inhibition performance of 2-hydrazino-4,6-dimethoxy-1,3,5-tirazine (DMeHT), 2,4-dihydrazino-6-methoxy-1,3,5-triaizine (DHMeT), and 2,4,6-tridydrazino-1,3,5-triaizne (TH₃) on steel corrosion in acidic media was examined using electrochemical techniques. The results showed 2,4-Ddihydrazino-6-methoxy-1,3,5-triaizine (DHMeT) gave the best corrosion protection performance among the other hydrazino derivatives even at a low concentration of 25 ppm (95%). The number of hydrazino groups play an important role in the corrosion inhibition, where the two hydrazine groups increased the electrostatic interactions between the protonated tested compounds, the negatively charged steel surface resulted from the adsorption of the chloride anions, and the presence of the methoxy group made the compound more reliable for formation of film protection on the surface of steel through the lone pair of oxygen atoms. Electrochemical Impedance Spectroscopy (EIS) measurements suggested that the corrosion process of steel in presence of the hydrazino-s-triazine derivatives (TH₃, DMeHT and DHMeT) were being controlled by the charge transfer reaction. Polarization curves indicated that the examined TH₃, DMeHT and DHMeT behaved as mixed type inhibitors. PMID:27258241

  6. Mechanism and toxicity research of benzalkonium chloride oxidation in aqueous solution by H2O2/Fe(2+) process.

    PubMed

    Zhang, Qian; Xia, Yu-Feng; Hong, Jun-Ming

    2016-09-01

    As widely used disinfectants, the pollution caused by benzalkonium chloride (BAC) has attracted a lot of attention in recent years. Since it is not suitable for biodegradation, BAC was degraded firstly by Fenton advanced oxidation technologies (AOTs) in this research to enhance the biodegradability of the pollutions. The result revealed that the optimal molar ratio of H2O2/Fe(2+) for BAC degradation was 10:1, and the COD removal rate was 32 %. To clarify the pathway of degradation, the technique of GC-MS was implemented herein to identify intermediates and the toxicity of those BAC intermediates were also novelty tested through microbial fuel cells (MFC). The findings indicated that ten transformation products including benzyl dimethyl amine and dodecane were formed during the H2O2/Fe(2+) processes, which means the degradation pathway of BAC was initiated both on the hydrophobic (alkyl chain) and hydrophilic (benzyl and ammonium moiety) region of the surfactant. The toxicity of BAC before and after treated by Fenton process was monitored through MFC system. The electricity generation was improved 337 % after BAC was treated by H2O2/Fe(2+) oxidation processes which indicated that the toxicity of those intermediates were much lower than BAC. The mechanism and toxicity research in this paper could provide the in-depth understanding to the pathway of BAC degradation and proved the possibility of AOTs for the pretreatment of a biodegradation process. PMID:27250091

  7. Micelle-Vesicle Transition by Cleavage of Disulfide Spacer Chain for Gemini Surfactant in Didodecyldimethylammonium Chloride Aqueous Solutions.

    PubMed

    Mizuhashi, Toshinari; Asakawa, Tsuyoshi; Ohta, Akio

    2015-01-01

    We examined the "micelle-vesicle transition" through the mixing effect of single-tailed thiol surfactants produced by the cleavage of gemini surfactants, [C12H25N(CH3)2CH2CH2SSCH2CH2N(CH3)2C12H25] 2Cl (C12SSC12), which have a disulfide bond in the spacer chain. Phase diagrams of C12H25N(CH3)2CH2CH2SHCl-didodecyldimethylammonium chloride (C12SH-DDAC) and C12SSC12-DDAC were determined by conductivity and pyrene fluorescence probe methods. The aggregate diameters were evaluated by dynamic light scattering (DLS). The critical vesicle concentration (CVC) was confirmed by the abrupt increase in the intensity of light scattering with excitation at 335 nm. Vesicle formation was confined to the DDAC-rich region of the C12SSC12-DDAC system, while the vesicle formation region for the C12SH-DDAC system spread out with the addition of dithiothreitol (DTT) to C12SSC12-DDAC. This implies that single-tailed surfactants can induce a more favorable environment for molecular packing of the vesicular surface. The micelle-vesicle transition occurs with disulfide spacer chain cleavage of gemini surfactants at a particular specific concentration range. PMID:26250426

  8. Comparison of the kinetic laws of the dissolution of bauxite and aluminum and iron(III) oxides and hydroxides in hydrochloric acid

    NASA Astrophysics Data System (ADS)

    Gololobova, E. G.; Gorichev, I. G.; Lainer, Yu. A.; Kozlov, K. V.

    2013-07-01

    The influence of the temperature and concentration of a hydrochloric acid solution on the dissolution kinetics of aluminum and iron(III) oxides and hydroxides and a natural sample of aluminum-containing raw materials, bauxite, is studied. The rate W of the transition of iron(III) ions from bauxite is higher than the rate of aluminum ion transition. The dependence of the fraction of a dissolved solid phase on time τ of dissolution of the oxides and hydroxides is determined, α = 1 — exp(- Asinh( Wτ)). The solubility of iron(III) chloride increases and that of aluminum chloride decreases as the HCl concentration increases. An empirical equation is proposed for the description of the dependence of the process rate on a series of parameters,.

  9. An experimental study of zinc chloride speciation from 300 to 600 °C and 0.5 to 2.0 kbar in buffered hydrothermal solutions

    USGS Publications Warehouse

    Cygan, G.L.; Hemley, J.J.; d'Angelo, W. M.

    1994-01-01

    The solubility of sphalerite (ZnS) was measured in KCl-HCl-H2O solutions at 300-600??C and 0.5-2.0 kbar. The silicate assemblage K-feldspar-muscovite (or andalusite)-quartz was used to buffer the solution to acid conditions, resulting in the total solubility reaction 2K+ + KAl2AlSi3O10(OH)2 + 6SiO2 + ZnS + nCl- = ZnCln(2-n) + 3KAlSi3O8 + H2S. (muscovite) (quartz) (sphalerite) (K-feldspar) A computer retrieval technique was used to derive average chloride ligand numbers for chlorozinc species at 0.25-2.0 molal total chloride. This technique mathematically solves for the average ligand number using a series of pertinent chemical relations at P and T. Mono- and di-chlorozinc species were found to predominate throughout the pressure-temperature-composition range investigated. The logarithms of the first and second dissociation constants for ZnCl20 were evaluated over the P-T range; for example, at 1 kbar, the values -0.41 and -1.42 were computed for the logarithm of the first dissociation constant, while -7.62 and -10.57 were computed for the logarithm of the second dissociation constant, for 400 and 500??C, respectively. Results are compared to past studies conducted at subcritical conditions and differ in that we find no evidence for more highly coordinated chloro-zinc species except possibly for ZnCl3- at 600??C, 1 and 2 kbar. Our results are consistent with electrostatic theory, which favors lower charged to neutral molecules in low dielectric-constant media. ?? 1994.

  10. RECLAMATION OF ALUMINUM FINISHING SLUDGES

    EPA Science Inventory

    The research study of the reclamation of aluminum-anodizing sludges was conducted in two sequential phases focused on enhanced dewatering of aluminum-anodizing sludges to produce commercial-strength solutions of aluminum sulfate, i.e., liquid alum. The use of high-pressure (14 to...

  11. Removal of copper (II) from aqueous solutions by flotation using polyaluminum chloride silicate (PAX-XL60 S) as coagulant and carbonate ion as activator.

    PubMed

    Ghazy, S E; Mahmoud, I A; Ragab, A H

    2006-01-01

    Flotation is a separation technology for removing toxic heavy metal ions from aqueous solutions. Here a simple and rapid flotation procedure is presented for the removal of copper(II) from aqueous solutions. It is based on the use of polyaluminum chloride silicate (PAX-XL60 S) as coagulant and flocculent, carbonate ion as activator and oleic acid (HOL) as surfactant. Both ion and precipitate flotation are included depending on the solution pH. Ion and precipitate flotation in the aqueous HOL-PAX-XL60 S-Cu2+-CO3(2-) system gave powerful preferential removal of Cu2+ (F -100%) over the HOL-PAX-XL60 S-Cu2+ system containing no CO3(2+) ion (F approximately 86%). The role of CO3(2-) ion is also evident from decreasing the dose of PAX-XL60 S from 700 mg l(-1) to 200 mg l(-1). The other parameters, influencing the flotation process, namely: metal ion, surfactant and PAX-XL60 S concentrations, ionic strength, temperature and foreign ions were examined. Moreover, the procedure was successfully applied to recover Cu2+ ions from different volumes up to 11 and from natural water samples. PMID:16457175

  12. Corrosion behaviour of 316L stainless steel and anti-corrosion materials in a high acidified chloride solution

    NASA Astrophysics Data System (ADS)

    Jin, Z. H.; Ge, H. H.; Lin, W. W.; Zong, Y. W.; Liu, S. J.; Shi, J. M.

    2014-12-01

    The corrosion behaviour of a type 316L (UNS S31603) stainless steel (SS) expansion joint in a simulated leaching solution of sediment on blast furnace gas pipeline in a power plant is investigated by using dynamic potential polarization curves, electrochemical impedance spectroscopy (EIS), optical microscope, atomic force microscope (AFM) and Scan Kelvin Probe (SKP). Severe general corrosion accompanied by pitting corrosion occurs on the type 316L SS surface in this solution. As the immersion period increases, the charge transfer resistance Rct decreases, the dissolution rate accelerates, the surface roughness increases and the surface potential difference enhances significantly. Then eight corrosion-resistant materials are tested, the corrosion rates of type 254SMo SS, type 2507 SS and TA2 are relatively minor in the solution. The corrosion resistance properties of TA2 is most excellent, indicating it would be the superior material choice for blast furnace gas pipeline.

  13. X-ray photoelectron spectroscopy surface analysis of aluminum ion stress in barley roots. [Hordeum vulgare

    SciTech Connect

    Millard, M.M.; Foy, C.D.; Coradetti, C.A.; Reinsel, M.D. )

    1990-06-01

    X-ray photoelectron spectroscopy (XPS) has been used to analyze root surface changes when Dayton barley (Hordeum vulgare) (Al tolerant) and Kearney barley (Al sensitive) seedlings were grown in nutrient solution in the presence and absence of 37.0 micromolar Al. The electron spectra from root surfaces contained strong lines in order of decreasing intensity from organic forms of carbon, oxygen, and nitrogen and weak lines due to inorganic elements in the form of anions and cations on the surface. The surface composition of root tips from Kearney was C, 65.6%; 0, 26.8%; N, 4.4% and tips from Dayton was C, 72.7%; O, 23.6%; N, 1.9%, grown in the absence of aluminum. Electron lines characteristic of nitrate, potassium, chloride, phosphate were also present in the spectra from those roots. Dayton roots grown in the presence of 37.0 micromolar aluminum contained 2.1% aluminum while Kearney contained 1.3% aluminum. The ratio of aluminum to phosphate was close to 1.0. Dayton roots usually contained twice as much aluminum phosphate in the surface region as Kearney. Dayton may be less susceptible to Al toxic effects by accumulation of aluminum phosphate on the root surface which then acts as a barrier to the transport of aluminum into the interior of the roots.

  14. Terbium chloride--aluminum chloride vapor system. II. Fluorescence

    SciTech Connect

    Caird, J.A.; Hessler, J.P.; Carnall, W.T.; Williams, C.W.

    1981-01-15

    Measurements of the fluorescence spectra and fluorescence decay kinetics of the vapor complex formed at elevated temperatures between TbCl/sub 3/ and AlCl/sub 3/ have been made in the 350 to 700 nm wavelength range. The principal lines in the spectra were identified as emission from the /sup 5/D/sub 4/, /sup 5/D/sub 3/, and the /sup 5/G/sub 6/ energy levels of the Tb/sup 3 +/ ion. The radiative lifetime of the /sup 5/D/sub 4/ level at low temperatures was found to be 3.88 ms, and was used to determine the oscillator strenghts of the /sup 5/D/sub 4/..-->../sup 7/F/sub J/ (J=0 through 6) transitions after their branching ratios were measured. The peak cross section for stimulated emission on the strong /sup 5/D/sub 4/..-->../sup 7/F/sub 5/ transition was found to be 2.87 x 10/sup -21/ cm/sup 2/ at lambda=543 nm. A population inversion of 10/sup 18/ cm/sup -3/ could produce a small signal gain of 30% per meter on this transition, indicating that laser emission may be possible at temperatures where sufficient vapor density can be obtained.

  15. Study of caffeine as corrosion inhibitors of carbon steel in chloride solution containing hydrogen sulfide using electrochemical impedance spectroscopy (EIS)

    NASA Astrophysics Data System (ADS)

    Solehudin, Agus; Berman, Ega Taqwali; Nurdin, Isdiriayani

    2015-09-01

    The corrosion behaviour of steel surface in the absence and presence of caffeine in 3.5% NaCl solution containing dissolved H2S gas is studied using electrochemical impedance spectroscopy (EIS). The experimental results of carbon steel corrosion in 3.5% NaCl solution containing 500 mg/l H2S at different caffeine concentrations showed that corrosion rate of carbon steel decreases with increasing of caffeine concentrations from 0 to 0,1 mmol/l. Whereas, the corrosion rate increase with increasing of caffeine concentrations from 1 to 10 mmol/l. It is clear that no inhibition efficiency increases with increasing inhibitor concentration. The optimum value of inhibition efficiency was 90% at a caffeine concentration of 0.1 mmol/l. This suggests that caffeine's performance as a corrosion inhibitor is more effective at a concentration of 0.1 mmol/l.

  16. Phonon spectroscopy of the low-energy excitations in the solid solutions of yttrium–rare-earth metal–aluminum garnets

    SciTech Connect

    Khazanov, E. N. Taranov, A. V.; Shevchenko, E. V.; Charnaya, E. V.

    2015-07-15

    The transport characteristics of thermal-frequency phonons and the specific heat of a series of single crystals of yttrium–rare-earth metal–aluminum garnet solid solutions are studied at the helium temperatures. It is found that the existence of low-energy levels of various origins, which are responsible for an increase in the specific heat, retards phonon transport by one–three orders of magnitude. The temperature dependences of specific heat and the kinetic characteristics of phonons have a similar character.

  17. Effect of the cation model on the equilibrium structure of poly-L-glutamate in aqueous sodium chloride solution

    NASA Astrophysics Data System (ADS)

    Marchand, Gabriel; Soetens, Jean-Christophe; Jacquemin, Denis; Bopp, Philippe A.

    2015-12-01

    We demonstrate that different sets of Lennard-Jones parameters proposed for the Na+ ion, in conjunction with the empirical combining rules routinely used in simulation packages, can lead to essentially different equilibrium structures for a deprotonated poly-L-glutamic acid molecule (poly-L-glutamate) dissolved in a 0.3M aqueous NaCl solution. It is, however, difficult to discriminate a priori between these model potentials; when investigating the structure of the Na+-solvation shell in bulk NaCl solution, all parameter sets lead to radial distribution functions and solvation numbers in broad agreement with the available experimental data. We do not find any such dependency of the equilibrium structure on the parameters associated with the Cl- ion. This work does not aim at recommending a particular set of parameters for any particular purpose. Instead, it stresses the model dependence of simulation results for complex systems such as biomolecules in solution and thus the difficulties if simulations are to be used for unbiased predictions, or to discriminate between contradictory experiments. However, this opens the possibility of validating a model specifically in view of analyzing experimental data believed to be reliable.

  18. Effect of the cation model on the equilibrium structure of poly-L-glutamate in aqueous sodium chloride solution.

    PubMed

    Marchand, Gabriel; Soetens, Jean-Christophe; Jacquemin, Denis; Bopp, Philippe A

    2015-12-14

    We demonstrate that different sets of Lennard-Jones parameters proposed for the Na(+) ion, in conjunction with the empirical combining rules routinely used in simulation packages, can lead to essentially different equilibrium structures for a deprotonated poly-L-glutamic acid molecule (poly-L-glutamate) dissolved in a 0.3M aqueous NaCl solution. It is, however, difficult to discriminate a priori between these model potentials; when investigating the structure of the Na(+)-solvation shell in bulk NaCl solution, all parameter sets lead to radial distribution functions and solvation numbers in broad agreement with the available experimental data. We do not find any such dependency of the equilibrium structure on the parameters associated with the Cl(-) ion. This work does not aim at recommending a particular set of parameters for any particular purpose. Instead, it stresses the model dependence of simulation results for complex systems such as biomolecules in solution and thus the difficulties if simulations are to be used for unbiased predictions, or to discriminate between contradictory experiments. However, this opens the possibility of validating a model specifically in view of analyzing experimental data believed to be reliable. PMID:26671388

  19. The effect of the electrochemical chloride extraction treatment on steel-reinforced mortar. Part II: Microstructural characterization

    SciTech Connect

    Marcotte, T.D.; Hansson, C.M.; Hope, B.B.

    1999-10-01

    A study has been made of the changes in cement composition and microstructures resulting from electrochemical chloride extraction applied to mortar samples in which the chlorides were added with the mixing water, ingressed by ponding with an NaCl solution, or both. After exposure for 1 year, specimens with and without chlorides were subjected to an electrochemical chloride extraction treatment. Microstructural analyses of fracture surfaces through the steel/mortar interface revealed a significant alteration of the cementitious phases. In untreated samples, calcium-silicon-rich phases consistent with Types I and II calcium silicate hydrate were observed. After the extraction treatment, these phases were not detectable and instead, sodium-rich, iron-rich, and calcium-aluminum-rich phases were observed.

  20. Evolution of the corrosion process of AA 2024-T3 in an alkaline NaCl solution with sodium dodecylbenzenesulfonate and lanthanum chloride inhibitors

    NASA Astrophysics Data System (ADS)

    Zhou, Biner; Wang, Yishan; Zuo, Yu

    2015-12-01

    The evolution of the corrosion process of AA 2024-T3 in 0.58 g L-1 NaCl solution (pH 10) with sodium dodecylbenzenesulfonate (SDBS) and lanthanum chloride inhibitors was studied with electrochemical and surface analysis methods. With the addition of the compounded LaCl3 and SDBS inhibitors, in the early stage the polarization behavior of AA 2024-T3 changed from active corrosion to passivation, and both the general corrosion and pitting corrosion were inhibited. However, with the immersion time extended, the passive behavior gradually disappeared and pitting happened at the Cu-rich phases. After 24 h immersion, the compounded inhibitors still showed good inhibition for general corrosion, but the polarization curve again presented the characteristic similar to active polarization. The compounded inhibitors also inhibited the pitting corrosion to some extent. The acting mechanism of the inhibitors SDBS and La3Cl on the corrosion process of AA 2024-T3 in the test solution was discussed.

  1. Evaluating a 'biotic ligand model' applied to chloride-enhanced Cd uptake by Brassica juncea from nutrient solution at constant Cd2+ activity.

    PubMed

    López-Chuken, Ulrico J; Young, Scott D; Guzmán-Mar, Jorge L

    2010-03-01

    Evidence of chloride-enhanced cadmium uptake by plants in soil experiments has been reported. However, it is still unclear whether this finding is due to increased rates of Cd2+ diffusion to plant roots or the direct uptake of complexes such as CdC1+. A controlled hydroponic experiment was undertaken to distinguish and quantify the uptake rates of free and inorganic-complexed cadmium and to model the uptake of cadmium by Indian mustard plants with a 'biotic ligand model'. Plants were treated with NaCl (0 to 200 mM) including equivalent Na2SO4 treatments. Cadmium speciation in solution was calculated using the WHAM-VI model. Results of the current trials showed that higher Cl-concentrations in solution generally resulted in greater cadmium accumulation by plants than predicted by the Cd2+ activity. Activities of Cd-chloro complexes showed the best correlations with the cadmium concentrations in the plants compared with the activity of Cd2+. The biotic ligand model showed a reasonable good fit for the plants when assuming competition by Cd2+ and CdCl+ for sorption sites at root level. The relative values of the two reaction constants suggest that root affinity for Cd2+ is 3.4 times greater than for CdCl+. Nevertheless this clearly indicates a substantial role for chloro-complexed cadmium accumulation. PMID:20426272

  2. Surface-enhanced Raman scattering and atomic force microscopy of brass electrodes in sulfuric acid solution containing benzotriazole and chloride ion

    SciTech Connect

    Rubim, J.C.; Kim, J.; Henderson, E.; Cotton, T.M. Ames Lab., IA Iowa State Univ., Ames )

    1993-01-01

    Three different methods were used to roughen brass (Cu/Zn = 67/33) electrodes in 0.5 M H[sub 2]SO[sub 4] containing 1.0 mM benzotriazole (BTAH): (1) polarization at +0.05 V vs. saturated calomel for 5 min; (2) immersion in the above solution for six hours; and (3) oxidation-reduction cycling in the presence of chloride ion. The surfaces prepared by the first two methods exhibited surface-enhanced Raman scattering (SERS) spectra of the polymeric complex [Cu(I)BTA][sub s]. The SERS spectrum obtained from electrodes prepared by the third method is very similar to that of [Cu(I)CIBTAH][sub 4]. Examination of the electrodes by atomic force microscopy (AFM) showed that a large number of grain boundary sites are formed by the roughening processes. This effect is attributed to the loss of zinc, which occurs during corrosion of the mirror-like, polished brass electrode surface in the sulfuric acid solution. 11 refs., 5 figs.

  3. Enrichment of Polychlorinated Biphenyls from Aqueous Solutions Using Fe3O4 Grafted Multiwalled Carbon Nanotubes with Poly Dimethyl Diallyl Ammonium Chloride

    PubMed Central

    Zeng, Shaolin; Cao, Yuting; Sang, Weiguo; Li, Tianhua; Gan, Ning; Zheng, Lei

    2012-01-01

    In this paper, Fe3O4 nanoparticles (Fe3O4 NPs) grafted carboxyl groups of multiwalled carbon nanotubes with cationic polyelectrolyte poly (dimethyldiallylammonium chloride) (PDDA) (MWCNTs-COO−/PDDA@Fe3O4), are successfully synthesized and used for the extraction of six kinds of major toxic polychorinated biphenyls (PCBs) from a large volume of water solution. The hydrophilicity of the PDDA cage can enhance the dispersibility of sorbents in water samples, and the superparamagnetism of the Fe3O4 NPs facilitate magnetic separation which directly led to the simplification of the extraction procedure. With the magnetic solid-phase extraction (MSPE) technique based on the MWCNTs-COO−/PDDA@Fe3O4 sorbents, it requires only 30 min to extract trace levels of PCBs from 500 mL water samples. When the eluate condensed to 1.0 mL, concentration factors for PCBs became over 500. The spiked recoveries of several real water samples for PCBs were in the range of 73.3–98.9% with relative standard deviations varying from 3.8% to 9.4%, reflecting good accuracy of the method. Therefore, preconcentration of trace level of PCBs by using this MWCNTs-COO−/PDDA@Fe3O4 sorbent, which are stable for multiple reuses, from water solution can be performed. PMID:22754371

  4. A high-salinity solution with calcium chloride enables RNase-free, easy plasmid isolation within 55 minutes.

    PubMed

    Sasagawa, Noboru; Koebis, Michinori; Yonemura, Yoji; Mitsuhashi, Hiroaki; Ishiura, Shoichi

    2013-12-01

    We dramatically improved a plasmid-isolation protocol based on the popular alkaline-sodium dodecyl sulfate plasmid isolation method. Our modified method provides significant time and cost savings. We used a modified solution during the neutralization step, which allowed us to skip several subsequent handling steps, saving a great amount of time. The plasmids purified by this method were of high quality, and the optical density ratio 260 and 280 was approximately 1.8. Plasmid DNA isolated by our method was of sufficient quality to perform subsequent restriction enzyme cuts and other downstream experiments, including budding yeast transformation, cultured cell transfection, and Caenorhabditis elegans injection experiments. PMID:24390365

  5. The unusual importance of activity coefficients for micelle solutions illustrated by an osmometry study of aqueous sodium decanoate and aqueous sodium decanoate + sodium chloride solutions.

    PubMed

    Sharma, Poonam; MacNeil, Jennifer A; Bowles, Justine; Leaist, Derek G

    2011-12-28

    Freezing-point and vapor-pressure osmometry data are reported for aqueous sodium decanoate (NaD) solutions and aqueous NaD + NaCl solutions. The derived osmotic coefficients are analyzed with a mass-action model based on the micelle formation reaction qNa(+) + nD(-) = (Na(q)D(n))(q-n) and Guggenheim equations for the micelle and ionic activity coefficients. Stoichiometric activity coefficients of the NaD and NaCl components and the equilibrium constant for micelle formation are evaluated. Illustrating the remarkable but not widely appreciated nonideal behavior of ionic surfactant solutions, the micelle activity coefficient drops to astonishingly low values, below 10(-7) (relative to unity for ideal solutions). The activity coefficients of the Na(+) and D(-) ions, raised to large powers of q and n, reduce calculated extents of micelle formation by up to 15 orders of magnitude. Activity coefficients, frequently omitted from the Gibbs equation, are found to increase the calculated surface excess concentration of NaD by up to an order of magnitude. Inflection points in the extent of micelle formation, used to calculate critical micelle concentration (cmc) lowering caused by added salt, provide unexpected thermodynamic evidence for the elusive second cmc. PMID:22037556

  6. PREPARATION OF URANIUM-ALUMINUM ALLOYS

    DOEpatents

    Moore, R.H.

    1962-09-01

    A process is given for preparing uranium--aluminum alloys from a solution of uranium halide in an about equimolar molten alkali metal halide-- aluminum halide mixture and excess aluminum. The uranium halide is reduced and the uranium is alloyed with the excess aluminum. The alloy and salt are separated from each other. (AEC)

  7. Effect of Microstructure on the Electrochemical Behavior of Ti-10 Mass% Mn Alloys in High Chloride Solution

    NASA Astrophysics Data System (ADS)

    Nishimura, Toshiyasu

    2016-02-01

    The effect of microstructure on the corrosion of heat-treated Ti-10 mass% Mn alloys was investigated by electrochemical impedance spectroscopy (EIS) in 10% NaCl solution of pH 0.5 at 97 °C. Sample of solution heat treatment (ST) had a single β phase, and samples subjected to the aging heat treatment at 600 °C had α phase precipitation in β phases. The EIS measurements showed that the corrosion resistance of the aging heat-treated samples showed lower values than ST sample, however, much higher values than pure Ti. Thus, Mn was effective to increase the corrosion resistance of Ti alloys. Laser micrographs of heat-treated samples indicated that α phase was selectively corroded and made the pit after the corrosion test. The transmission electron microscope (TEM)-energy dispersive x-ray spectrometry (EDXS) analyses showed that the Mn content was 9 mass% in the β phase and 0.7 mass% in α phase. Hence, it was understood that less-Mn α phase was selectively corroded in the corrosion test. However, as compared with pure Ti, the aging heat-treated samples showed much higher resistance against the corrosion by the 0.7 mass% Mn in α phase. Finally, it was concluded that it was possible to keep the high corrosion resistance for heat-treated Ti-10 mass% Mn alloy by controlling the microstructure of α phase.

  8. Effect of sodium chloride on solute-solvent interactions in aqueous polyethylene glycol-sodium sulfate two-phase systems.

    PubMed

    da Silva, Nuno R; Ferreira, Luisa A; Madeira, Pedro P; Teixeira, José A; Uversky, Vladimir N; Zaslavsky, Boris Y

    2015-12-18

    Partition behavior of eight small organic compounds and six proteins was examined in poly(ethylene glycol)-8000-sodium sulfate aqueous two-phase systems containing 0.215M NaCl and 0.5M osmolyte (sorbitol, sucrose, TMAO) and poly(ethylene glycol)-10000-sodium sulfate-0.215M NaCl system, all in 0.01M sodium phosphate buffer, pH 6.8. The differences between the solvent properties of the coexisting phases (solvent dipolarity/polarizability, hydrogen bond donor acidity, and hydrogen bond acceptor basicity) were characterized with solvatochromic dyes using the solvatochromic comparison method. Differences between the electrostatic properties of the phases were determined by analysis of partitioning of sodium salts of dinitrophenylated (DNP-) amino acids with aliphatic alkyl side-chain. The partition coefficients of all compounds examined (including proteins) were described in terms of solute-solvent interactions. The results obtained in the study show that solute-solvent interactions of nonionic organic compounds and proteins in polyethylene glycol-sodium sulfate aqueous two-phase system change in the presence of NaCl additive. PMID:26615710

  9. Time exposure studies on stress corrosion cracking of aluminum 2014-T6, 2219-T87, 2014-T651, 7075-T651, and titanium 6Al-4V

    NASA Technical Reports Server (NTRS)

    Terrell, J.

    1973-01-01

    The effect of a constant applied stress in crack initiation of aluminum 2014-T6, 2219-T87, 2014-T651, 7075-T651 and titanium 6Al-4V has been investigated. Aluminum c-ring specimens (1-inch diameter) and u-band titanium samples were exposed continuously to a 3.5% NaCl solution (pH 7) and organic fluids of ethyl, methyl, and iso-propyl alcohol (reagent purity), and demineralized distilled water. Corrosive action was observed to begin during the first and second day of constant exposure as evidenced by accumulation of hydrogen bubbles on the surface of stressed aluminum samples. However, titanium stressed specimens showed no reactions to its environment. Results of this investigation seems to suggest that aluminum 2014-T6, aluminum 7075-T651 and aluminum 2014-T651 are susceptible to stress corrosion cracking in chloride solution (NaCl), while aluminum 2219-T87 seem to resist stress corrosion cracking in sodium chloride at three levels of stress (25%, 50%, and 75% Y.S.). In organic fluids of methyl, ethyl, and iso-propyl alcohol, 2014-T6 and 7075-T651 did not fail by SCC; but 2014-T651 was susceptible to SCC in methly alcohol, but resistant in ethyl alcohol, iso-propyl alcohol and demineralized distilled water.

  10. Purifying transplutonium elements from iron, zirconium, and aluminum by extraction with D2EHPA from citrate solution

    SciTech Connect

    Kasimov, F.D.; Gordeev, Ya.N.; Kovanseva, S.N.; Kasimova, V.A.; Nikolaev, V.M.; Skobelev, N.F.; Filimonov, V.T.; Yadovin, A.A.

    1987-03-01

    A study has been made on the effects of various factors on the zirconium extraction kinetics in the system consisting of citric acid with di-(2-ethylhexyl) phosphoric acid. It has been found that zirconium, iron (III), and aluminum are extracted much more slowly than the transplutonium elements (TPE). The process can be operated under nonequilibrium conditions to increase the separation factors considerably, which has been employed to improve the purification of TPE.

  11. Effect of bicarbonate ion additives on pitting corrosion of type 316L stainless steel in aqueous 0.5 M sodium chloride solution

    SciTech Connect

    Park, J.J.; Pyun, S.I.; Lee, W.J.; Kim, H.P.

    1999-04-01

    The effect of bicarbonate ions (HCO{sub 3}{sup {minus}}) on pitting corrosion of type 316L stainless steel (SS, UNS S3 1603) was investigated in aqueous 0.5 M sodium chloride (NaCl) solution using potentiodynamic polarization, the abrading electrode technique, alternating current (AC) impedance spectroscopy combined with x-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Addition of HCO{sub 3}{sup {minus}} ions to NaCl solutions extended the passive potential region in width and, at the same time, raised the pitting potential in value on the potentiodynamic polarization curve. Potentiostatic current transients obtained from the moment just after interrupting the abrading action showed the repassivation rate of propagating pits increased and that the pit growth rate decreased with increasing HCO{sub 3}{sup {minus}} ion concentration. Over the whole applied potential, the oxide film resistance was higher in the presence of HCO{sub 3}{sup {minus}} ions. The pit number density decreased with increasing HCO{sub 3}{sup {minus}} ion concentration. Moreover, addition of HCO{sub 3}{sup {minus}} ions to NaCl solutions retarded lateral pit growth, while promoting downward pit growth from the surface. The bare surface of the specimen repassivated preferentially along the pit mouth and walls, compared to the pit bottom, as a result of formation of a surface film with a high content of protective mixed ferrous-chromous carbonate ([Fe,Cr]CO{sub 3}) that formed from preferential adsorption of HCO{sub 3}{sup {minus}} ions.

  12. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  13. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium chloride. 184.1138 Section 184.1138...

  14. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  15. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  16. PREPARATION OF ACTINIDE-ALUMINUM ALLOYS

    DOEpatents

    Moore, R.H.

    1962-09-01

    BS>A process is given for preparing alloys of aluminum with plutonium, uranium, and/or thorium by chlorinating actinide oxide dissolved in molten alkali metal chloride with hydrochloric acid, chlorine, and/or phosgene, adding aluminum metal, and passing air and/or water vapor through the mass. Actinide metal is formed and alloyed with the aluminum. After cooling to solidification, the alloy is separated from the salt. (AEC)

  17. Removal of coagulant aluminum from water treatment residuals by acid.

    PubMed

    Okuda, Tetsuji; Nishijima, Wataru; Sugimoto, Mayo; Saka, Naoyuki; Nakai, Satoshi; Tanabe, Kazuyasu; Ito, Junki; Takenaka, Kenji; Okada, Mitsumasa

    2014-09-01

    Sediment sludge during coagulation and sedimentation in drinking water treatment is called "water treatment residuals (WTR)". Polyaluminum chloride (PAC) is mainly used as a coagulant in Japan. The recycling of WTR has been desired; one method for its reuse is as plowed soil. However, WTR reuse in this way is inhibited by the aluminum from the added PAC, because of its high adsorption capacity for phosphate and other fertilizer components. The removal of such aluminum from WTR would therefore be advantageous for its reuse as plowed soil; this research clarified the effect of acid washing on aluminum removal from WTR and on plant growth in the treated soil. The percentage of aluminum removal from raw WTR by sulphuric acid solution was around 90% at pH 3, the percentage decreasing to 40% in the case of a sun-dried sample. The maximum phosphate adsorption capacity was decreased and the available phosphorus was increased by acid washing, with 90% of aluminum removal. The enhancement of Japanese mustard spinach growth and the increased in plant uptake of phosphates following acid washing were observed. PMID:24835954

  18. Moessbauer spectroscopy study on the corrosion resistance of plasma nitrided ASTM F138 stainless steel in chloride solution

    SciTech Connect

    Souza, S.D. de; Olzon-Dionysio, M.; Basso, R.L.O.; Souza, S. de

    2010-10-15

    Plasma nitriding of ASTM F138 stainless steel samples has been carried out using dc glow discharge under 80% H{sub 2}-20% N{sub 2} gas mixture, at 673 K, and 2, 4, and 7 h time intervals, in order to investigate the influence of treatment time on the microstructure and the corrosion resistance properties. The samples were characterized by scanning electron microscopy, glancing angle X-ray diffraction and conversion electron Moessbauer spectroscopy, besides electrochemical tests in NaCl aerated solution. A modified layer of about 6 {mu}m was observed for all the nitrided samples, independent of nitriding time. The X-ray diffraction analysis shows broad {gamma}{sub N} phase peaks, signifying a great degree of nitrogen supersaturation. Besides {gamma}{sub N,} the Moessbauer spectroscopy results indicated the occurrence of {gamma}' and {epsilon} phases, as well as some other less important phases. Corrosion measurements demonstrate that the plasma nitriding time affects the corrosion resistance and the best performance is reached at 4 h treatment. It seems that the {epsilon}/{gamma}' fraction ratio plays an important role on the resistance corrosion. Additionally, the Moessbauer spectroscopy was decisive in this study, since it was able to identify and quantify the iron phases that influence the corrosion resistance of plasma nitrided ASTM F138 samples.

  19. [Sodium chloride 0.9%: nephrotoxic crystalloid?].

    PubMed

    Dombre, Vincent; De Seigneux, Sophie; Schiffer, Eduardo

    2016-02-01

    Sodium chloride 0.9%, often incorrectly called physiological saline, contains higher concentration of chloride compared to plasma. It is known that the administration of sodium chloride 0.9% can cause hyperchloremic metabolic acidosis in a reproducible manner. The elevated chloride concentration in 0.9% NaCl solution can also adversely affect renal perfusion. This effect is thought to be induced by hyperchloremia that causes renal artery vasoconstriction. For these reasons, the use of 0.9% NaCl solution is raising attention and some would advocate the use of a more "physiological" solution, such as balanced solutions that contain a level of chloride closer to that of plasma. Few prospective, randomized, controlled trials are available today and most were done in a perioperative setting. Some studies suggest that the chloride excess in 0.9% NaCl solution could have clinical consequences; however, this remains to be established by quality randomized controlled trials. PMID:26999998

  20. Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution

    PubMed Central

    Perito, Brunella; Giorgetti, Emilia; Marsili, Paolo

    2016-01-01

    Summary Silver nanoparticles (AgNPs) have increasingly gained importance as antibacterial agents with applications in several fields due to their strong, broad-range antimicrobial properties. AgNP synthesis by pulsed laser ablation in liquid (PLAL) permits the preparation of stable Ag colloids in pure solvents without capping or stabilizing agents, producing AgNPs more suitable for biomedical applications than those prepared with common, wet chemical preparation techniques. To date, only a few investigations into the antimicrobial effect of AgNPs produced by PLAL have been performed. These have mainly been performed by ablation in water with nanosecond pulse widths. We previously observed a strong surface-enhanced Raman scattering (SERS) signal from such AgNPs by “activating” the NP surface by the addition of a small quantity of LiCl to the colloid. Such surface effects could also influence the antimicrobial activity of the NPs. Their activity, on the other hand, could also be affected by other parameters linked to the ablation conditions, such as the pulse width. The antibacterial activity of AgNPs was evaluated for NPs obtained either by nanosecond (ns) or picosecond (ps) PLAL using a 1064 nm ablation wavelength, in pure water or in LiCl aqueous solution, with Escherichia coli and Bacillus subtilis as references for Gram-negative and Gram-positive bacteria, respectively. In all cases, AgNPs with an average diameter less than 10 nm were obtained, which has been shown in previous works to be the most effective size for bactericidal activity. The measured zeta-potential values were very negative, indicating excellent long-term colloidal stability. Antibacterial activity was observed against both microorganisms for the four AgNP formulations, but the ps-ablated nanoparticles were shown to more effectively inhibit the growth of both microorganisms. Moreover, LiCl modified AgNPs were the most effective, showing minimum inhibitory concentration (MIC) values in a

  1. Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution.

    PubMed

    Perito, Brunella; Giorgetti, Emilia; Marsili, Paolo; Muniz-Miranda, Maurizio

    2016-01-01

    Silver nanoparticles (AgNPs) have increasingly gained importance as antibacterial agents with applications in several fields due to their strong, broad-range antimicrobial properties. AgNP synthesis by pulsed laser ablation in liquid (PLAL) permits the preparation of stable Ag colloids in pure solvents without capping or stabilizing agents, producing AgNPs more suitable for biomedical applications than those prepared with common, wet chemical preparation techniques. To date, only a few investigations into the antimicrobial effect of AgNPs produced by PLAL have been performed. These have mainly been performed by ablation in water with nanosecond pulse widths. We previously observed a strong surface-enhanced Raman scattering (SERS) signal from such AgNPs by "activating" the NP surface by the addition of a small quantity of LiCl to the colloid. Such surface effects could also influence the antimicrobial activity of the NPs. Their activity, on the other hand, could also be affected by other parameters linked to the ablation conditions, such as the pulse width. The antibacterial activity of AgNPs was evaluated for NPs obtained either by nanosecond (ns) or picosecond (ps) PLAL using a 1064 nm ablation wavelength, in pure water or in LiCl aqueous solution, with Escherichia coli and Bacillus subtilis as references for Gram-negative and Gram-positive bacteria, respectively. In all cases, AgNPs with an average diameter less than 10 nm were obtained, which has been shown in previous works to be the most effective size for bactericidal activity. The measured zeta-potential values were very negative, indicating excellent long-term colloidal stability. Antibacterial activity was observed against both microorganisms for the four AgNP formulations, but the ps-ablated nanoparticles were shown to more effectively inhibit the growth of both microorganisms. Moreover, LiCl modified AgNPs were the most effective, showing minimum inhibitory concentration (MIC) values in a restricted

  2. The study of the varying characteristics of cathodic regions for defective coating in 3.5% sodium chloride solution by EIS and WBE

    NASA Astrophysics Data System (ADS)

    Wang, Haijie; Wang, Jia; Wang, Wei; Zhang, Wei

    2015-04-01

    The current distributions over carbon steel under iron red alkyd primer exposed to 3.5% sodium chloride solution were mapped using the wire beam electrode (WBE). The electrochemical impedance spectroscopy (EIS) of the WBE was carried out to analyze the performance of coating delamination and corrosion behavior of carbon steel beneath defective coating. The EIS data revealed that protective capability of coating decreased with immersion time and the degree of cathodic delamination showed a rapid rise. The current density distribution of WBE indicated that cathodic sites was located at the defect at the beginning of immersion and gradually spread into the intact coating. The cathodic regions were distinguished from the anodic area and distributed over the WBE. The changes of cathodic sites could reflect the deterioration process of defective coating. The cathodic area ratio was a more useful parameter than the cathodic delamination degree to evaluate the coating cathodic delamination. The polarity reversals of electrodes at the defect and beneath coating were observed. A simple discussion of relationship between the blister and the polarity reversal was made from a standpoint of electrochemical distribution. WBE method was able to map and record the changes of local cathodic sites beneath defective coating in real time, which could provide more detailed information about the local degradation of coating.

  3. Totally solution-processed CuInS2 solar cells based on chloride inks: reduced metastable phases and improved current density

    NASA Astrophysics Data System (ADS)

    Dehghani, Mehdi; Behjat, Abbas; Tajabadi, Fariba; Taghavinia, Nima

    2015-03-01

    Planar superstrate CuInS2 (CIS) solar cell devices are fabricated using totally solution-processed deposition methods. These Cd-free devices are structured by FTO/TiO2/In2S3/CIS/carbon, where TiO2 and In2S3 are deposited by spray pyrolysis, and a CIS film is deposited using spin-coating followed by annealing at 250 °C. The pasted carbon layer is utilized as the anode. No further sulfurization or selenization is employed. The Cu/In ratio in the ink is found as a critical factor affecting the morphology and crystallinity of the film as well as the photovoltaic performance of the device. An optimum Cu/In = 1.05 results in large-grain films with sharp diffraction peaks and, subsequently, optimal series resistance and shunt conductance. It is also found that the chloride-based ink results in CIS films with considerably reduced metastable phases, compared to the conventional acetate-based inks. A current density of 23.6 mA cm-2 is obtained for the best devices, leading to a conversion efficiency of 4.1%.

  4. Microgel-like aggregates of isotactic and atactic poly(methacrylic acid) chains in aqueous alkali chloride solutions as evidenced by light scattering.

    PubMed

    Sitar, Simona; Aseyev, Vladimir; Kogej, Ksenija

    2014-10-21

    A comparative light-scattering study of isotactic and atactic poly(methacrylic acid), iPMA and aPMA, respectively, in aqueous solutions with added alkali chlorides, XCl (X = Li, Na, Cs), at 25 °C and XCl concentration of 0.1 mol L(-1), demonstrates that both PMA isomers are strongly associated at low degrees of neutralization, αN (= 0 for aPMA and 0.25 for iPMA), in the presence of all XCls. The shape parameter ρ and the scattering functions suggest that aggregates have the characteristics of microgel particles, with a dense core surrounded by a less dense shell. The extent of aggregation depends on the stereoregular structure of the polymer and on the type of the added cation. Li(+) and Na(+) ions support aggregation better than Cs(+) ions. Besides, iPMA chains are more strongly aggregated than aPMA chains and form particles with a denser core. A model of the aggregation process is suggested for iPMA. At high αN, a slow diffusive process (so-called extraordinary or anomalous mode in diffusion of polyelectrolytes), arising from electrostatic interactions between charged chains, is observed for both PMAs. Results suggest that under the same experimental conditions iPMA is effectively more charged than aPMA. The role of ions in the slow-mode phenomenon is less pronounced than in aggregation. PMID:25137480

  5. Corrosion resistance of AA6063-Type Al-Mg-Si alloy by silicon carbide in sodium chloride solution for marine application

    NASA Astrophysics Data System (ADS)

    Fayomi, Ojo Sunday Isaac; Abdulwahab, Malik; Popoola, Abimbola Patricia Idowu; Asuke, Ferdinand

    2015-12-01

    The present work focused on corrosion inhibition of AA6063 type (Al-Mg-Si) alloy in sodium chloride (NaCl) solution with a silicon carbide inhibitor, using the potentiodynamic electrochemical method. The aluminium alloy surface morphology was examined, in the as-received and as-corroded in the un-inhibited state, with scanning electron microscopy equipped with energy dispersive spectroscopy (SEM-EDS). The results obtained via linear polarization indicated a high corrosion potential for the unprotected as-received alloy. Equally, inhibition efficiency as high as 98.82% at 10.0 g/v silicon carbide addition was obtained with increased polarization resistance ( R p), while the current density reduced significantly for inhibited samples compared to the un-inhibited aluminium alloy. The adsorption mechanism of the inhibitor aluminium alloy follows the Langmuir adsorption isotherm. This shows that the corrosion rate of aluminium alloy with silicon carbide in NaCl environment decreased significantly with addition of the inhibitor.

  6. Vinyl chloride

    Integrated Risk Information System (IRIS)

    Vinyl chloride ; CASRN 75 - 01 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  7. Methyl chloride

    Integrated Risk Information System (IRIS)

    Methyl chloride ; CASRN 74 - 87 - 3 ( 07 / 17 / 2001 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for

  8. Ethyl chloride

    Integrated Risk Information System (IRIS)

    Ethyl chloride ; CASRN 75 - 00 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  9. Benzyl chloride

    Integrated Risk Information System (IRIS)

    Benzyl chloride ; CASRN 100 - 44 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  10. Hydrogen chloride

    Integrated Risk Information System (IRIS)

    Hydrogen chloride ; CASRN 7647 - 01 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogeni

  11. Mepiquat chloride

    Integrated Risk Information System (IRIS)

    Mepiquat chloride ; CASRN 24307 - 26 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogen

  12. Allyl chloride

    Integrated Risk Information System (IRIS)

    Allyl chloride ; CASRN 107 - 05 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  13. Acetyl chloride

    Integrated Risk Information System (IRIS)

    Acetyl chloride ; CASRN 75 - 36 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  14. The detection of μm and sub-μm droplets of aqueous solutions of sodium chloride and sodium sulfate

    NASA Astrophysics Data System (ADS)

    Ueno, Yasuo; Williams, Alan

    μm and sub-μm droplets of aqueous NaCl and Na 2SO 4 solutions were quantitatively identified by a chemical spot technique using thin and ultra-thin films of polyvinyl alcohol-reagent mixture. A comparison has been made between theoretical and experimental calibration curves under various conditions with respect to the thickness of the film and different reagent concentration for the detection of chloride or sulfate. Droplets generated by the atomization of aqueous NaCl or Na 2SO 4 solution were collected on these polyvinyl alcohol-reagent films. The spots impressed on the films were measured by an optical microscope. Calibration curves relating the spot and droplet diameters were experimentally measured. It was found that each of the calibration curves could be expressed by a relation Dd3 = Kd2s, where Dd is the volume average diameter of the droplets, ds the surface average diameter of the spots and K is a calibration curve constant. The meaning of K is discussed. A linear relationship has been found between the ratio of an experimental calibration curve constant to a theoretical one and the concentration of the reagent in the film. Then the following equation was obtained: K (exptl)/K (theor.) = 0.29A , where A is the concentration of the reagent in the film (molℓ -1). This equation is useful in estimating the values of different experimental calibration curve constants. The minimum diameter of the droplets that can be identified by this technique is 0.2 μm.

  15. Influence of the anions on the N-cationic benzethonium salts in the solid state and solution: Chloride, bromide, hydroxide and citrate hydrates

    NASA Astrophysics Data System (ADS)

    Paradies, Henrich H.; Reichelt, Hendrik

    2016-06-01

    The crystal structures of the hydrated cationic surfactant benzethonium (Bzth) chloride, bromide, hydroxide, and citrate have been determined by X-ray diffraction analysis and compared with their structures in solution well above their critical micelle concentration. The differences in the nature of the various anions of the four Bzth-X materials lead to unique anion environments and 3-D molecular arrangements. The water molecule in the monoclinic Bzth-Cl or Bzth-Br forms is hydrogen bonded to the halides and particularly to the hydrogens of the methoxy groups of the Bzth moiety notwithstanding the weak Brønsted acidity of the methoxy hydrogens. The citrate strongly interacts with the hydrogens of the methoxy group forming an embedded anionic spherical cluster of a radius of 2.6 Å. The Bzth-OH crystallizes in a hexagonal lattice with two water molecules and reveals free water molecules forming hydrogen bonded channels through the Bzth-OH crystal along the c-axis. The distances between the cationic nitrogen and the halides are 4.04 Å and 4.20 Å, significantly longer than expected for typical van der Waals distances of 3.30 Å. The structures show weakly interacting, alternating apolar and polar layers, which run parallel to the crystallographic a-b planes or a-c planes. The Bzth-X salts were also examined in aqueous solution containing 20% (v/v) ethanol and 1.0 % (v/v) glycerol well above their critical micelle concentration by small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS). The [1,1,1] planes for the Bzth Cl or Br, the [0,0,2] and [1,1,0] planes for the Bzth-citrate, the [2,-1,0] planes and the [0,0,1] planes for the Bzth-OH found in the crystalline phase were also present in the solution phase, accordingly, the preservation of these phases are a strong indication of periodicity in the solution phase.

  16. Molecular Dynamics Study of Solute Pinning Effects on Grain Boundary Migration in the Aluminum Magnesium Alloy System

    NASA Astrophysics Data System (ADS)

    Rahman, Md. Jahidur; Zurob, Hatem S.; Hoyt, Jeffrey J.

    2016-04-01

    Molecular dynamics simulation, combined with the artificial driving force technique, has been used to study solute interactions with migrating grain boundaries, especially low angle boundaries, in the Al-Mg alloy system. The motion of [112] symmetric tilt boundaries was investigated employing two different approaches at 300 K (27 °C). In the first approach, where solute atoms are segregated and surround the intrinsic dislocations at the grain boundary, a strong solute pinning effect was observed at all misorientations and at different Mg concentrations. A minimum driving force is found to be required for overcoming the barrier produced by the segregated solute at the boundary and a high magnitude of threshold force was observed in all alloys examined. In the alternative approach, where solutes are distributed in a confined region away from the grain boundary, we find that the velocity-driving force behavior in the high driving pressure regime depends on solute concentration, consistent with a recent solute pinning model by Hersent et al. The distributed solute approach provided less pining effect on low angle grain boundary migration compared to that of segregated solutes. The relationship between the restraining force and the solute concentration was computed and, when fit to the Hersent et al. analysis, the solute pinning constant was found to be α = 35 ± 7 MPa for a 7.785 deg boundary in the Al-Mg binary system.

  17. CORROSION PROTECTION OF ALUMINUM

    DOEpatents

    Dalrymple, R.S.; Nelson, W.B.

    1963-07-01

    Treatment of aluminum-base metal surfaces in an autoclave with an aqueous chromic acid solution of 0.5 to 3% by weight and of pH below 2 for 20 to 50 hrs at 160 to 180 deg C produces an extremely corrosion-resistant aluminum oxidechromium film on the surface. A chromic acid concentration of 1 to 2% and a pH of about 1 are preferred. (D.C.W.)

  18. Corrosion Protection of Aluminum

    DOEpatents

    Dalrymple, R. S.; Nelson, W. B.

    1963-07-01

    Treatment of aluminum-base metal surfaces in an autoclave with an aqueous chromic acid solution of 0.5 to 3% by weight and of pH below 2 for 20 to 50 hrs at 160 to 180 deg C produces an extremely corrosion-resistant aluminum oxidechromium film on the surface. A chromic acid concentration of 1 to 2% and a pH of about 1 are preferred.

  19. Aluminum Hydroxide

    MedlinePlus

    Aluminum hydroxide is used for the relief of heartburn, sour stomach, and peptic ulcer pain and to ... Aluminum hydroxide comes as a capsule, a tablet, and an oral liquid and suspension. The dose and ...

  20. Aluminum-ferricyanide battery

    SciTech Connect

    Marsh, C.; Licht, S.L.

    1993-11-29

    A battery capable of producing high current densities with high charge capacity is described which includes an aluminum anode, a ferricyanide electrolyte and a second electrode capable of reducing ferricyanide electrolyte which is either dissolved in an alkaline solution or alkaline seawater solution. The performance of the battery is enhanced by high temperature and high electrolyte flow rates.

  1. Metal chloride cathode for a battery

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V. (Inventor); Distefano, Salvador (Inventor); Bankston, C. Perry (Inventor)

    1991-01-01

    A method of fabricating a rechargeable battery is disclosed which includes a positive electrode which contains a chloride of a selected metal when the electrode is in its active state. The improvement comprises fabricating the positive electrode by: providing a porous matrix composed of a metal; providing a solution of the chloride of the selected metal; and impregnating the matrix with the chloride from the solution.

  2. RECOVERY OF ALUMINUM FROM FISSION PRODUCTS

    DOEpatents

    Blanco, R.E.; Higgins, I.R.

    1962-11-20

    A method is given for recovertng aluminum values from aqueous solutions containing said values together with fission products. A mixture of Fe/sub 2/O/ sub 3/ and MnO/sub 2/ is added to a solution containing aluminum and fission products. The resulting aluminum-containing supernatant is then separated from the fission product-bearing metal oxide precipitate and is contacted with a cation exchange resin. The aluminum sorbed on the resin is then eluted and recovered. (AEC)

  3. First-principles study on stability of transition metal solutes in aluminum by analyzing the underlying forces

    SciTech Connect

    Liu, Wei; Xu, Yichun; Li, Xiangyan; Wu, Xuebang Liu, C. S.; Liang, Yunfeng; Wang, Zhiguang

    2015-05-07

    Although there have been some investigations on behaviors of solutes in metals under strain, the underlying mechanism of how strain changes the stability of a solute is still unknown. To gain such knowledge, first-principles calculations are performed on substitution energy of transition metal solutes in fcc Al host under rhombohedral strain (RS). Our results show that under RS, substitution energy decreases linearly with the increase of outermost d radius r{sub d} of the solute due to Pauli repulsion. The screened Coulomb interaction increases or decreases the substitution energy of a solute on condition that its Pauling electronegativity scale ϕ{sub P} is less or greater than that of Al under RS. This paper verifies a linear relation of substitution energy change versus r{sub d} and ϕ{sub P} under RS, which might be instructive for composition design of long life alloys serving in high stress condition.

  4. Influence of composition and processing parameters on the properties of solution-processed aluminum phosphate oxide (AlPO) thin films

    NASA Astrophysics Data System (ADS)

    Norelli, Kevin M.; Plassmeyer, Paul N.; Woods, Keenan N.; Glassy, Benjamin A.; Knutson, Christopher C.; Beekman, Matt; Page, Catherine J.

    2016-05-01

    The effects of precursor solution concentration, composition, and spin-processing parameters on the thickness and electrical properties of ultra-smooth aluminum oxide phosphate (Al2O3-3x(PO4)2x or "AlPO") thin films prepared using aqueous solutions are reported. Compositions were verified by electron probe micro-analysis and range from Al2O1.5(PO4) to AlPO4 (x = P:Al from 0.5 to 1.0). Film thicknesses were determined using X-ray reflectivity measurements and were found to depend systematically on solution concentration, P:Al ratio, and spin-speed. Metal-insulator-semiconductor devices were fabricated to determine electrical properties as a function of composition. As the P:Al ratio increased from 0.5 to 1.0, the dielectric constant decreased from 6.0 to 4.6, leakage currents increased from 0.45 to 65 nA cm-2 at 1 MV cm-1 and dielectric breakdown (defined as leakage currents >10 μA cm-2) decreased from 9.74 to 2.84 MV cm-1. These results establish composition, concentration, and spin-speed for the production of AlPO films with targeted thicknesses and electrical properties.

  5. Time exposure studies on stress corrosion cracking of aluminum 2014-T6, aluminum 7075-T651, and titanium 6Al-4V

    NASA Technical Reports Server (NTRS)

    Terrell, J.

    1972-01-01

    The effect of a constant applied stress in crack initiation of aluminum 2014-T6, 7075-T651 and titanium 6A1-4V has been investigated. Aluminum c-ring specimens (1-inch diameter) and u-band titanium samples were exposed continuously to a 3.5% NaCl solution (pH 6) and organic fluids of ethyl, methyl, and iso-propyl alcohol (reagent purity). Corrosive action was observed to begin during the first and second day of constant exposure as evidenced by accumulation of hydrogen bubbles on the surface of stressed aluminum samples. However, a similar observation was not noted for titanium stressed specimens. Results of this investigation seems to suggest that aluminum 2014-T6, aluminum 7075-T651 are susceptible to stress corrosion cracking in chloride solution (NaCl); while they (both alloys) seem to resist stress corrosion cracking in methyl alcohol, ethyl alcohol, iso-propyl alcohol, and demineralized distilled water. Titanium 6A1-4V showed some evidence of susceptibility to SCC in methanol, while no such susceptibility was exhibited in ethanol, iso-propyl alcohol and demineralized distilled water.

  6. Electrical and Surface Morphology of Polyvinylchloride Composites Filled with Aluminum Powder

    SciTech Connect

    Singh, Dolly; Kishore, Sangeeta; Singh, N. L.

    2011-07-15

    In this work, the electrical and surface morphology of polyvinyl chloride (PVC) composites filled with different concentration of aluminum powder varying from 0 to 40 wt.% have been prepared by solution costing method. The electrical conductivity of these composites were investigated in the frequency range 100 Hz-10 MHz at room temperature. The conductivity of the composites system exhibited a strong frequency dependence particularly in the vicinity of percolation threshold (20 wt.%). It was observed that the electrical conductivity gradually increased with filler concentration and frequency and explained in terms of hopping conduction mechanism. The electrical conductivity of the composites obeys universal power law (i.e. {sigma} = Af{sup n}), where, n is power exponent. The scanning electron microscope (SEM) micrographs indicate the agglomeration of aluminum particles dispersed within the PVC at the higher aluminum concentration, yielding a conductive path through the composites. It is also corroborated with electrical conductivity result.

  7. EVALUATION OF LOW TEMPERATURE ALUMINUM DISSOLUTION IN TANK 51

    SciTech Connect

    Pike, J

    2008-09-04

    loss from a quiescent tank; and an evaluation of the aluminum dissolution rate model and actual dissolution rate. LTAD was successfully completed in Tank 51 with minimal waste tank changes. The following general conclusions may be drawn about the LTAD process: (1) Dissolution at about 60 C for 46 days dissolved 64% of the aluminum from the sludge slurry. (2) The aluminum-laden leach solution decanted to Tank 11 can be blended with a wide variety of supernates without risk of precipitating the dissolved aluminum based on thermodynamic chemical equilibrium models. (3) Uranium and plutonium leached into solution without corresponding leaching of iron or metal other than aluminum, but the total mass leached was a small fraction of the total uranium and plutonium in the sludge. (4) The concentration of uranium and plutonium in the leach solution was indistinguishable from other tank farm supernates, thus, the leach solutions can be managed relative to the risk of criticality like any other supernate. (5) A small amount of mercury leached into solution from the sludge causing the liquid phase concentration to increase 6 to 10 fold, which is consistent with the 4 to 14 fold increase observed during the 1982 aluminum dissolution demonstration. (6) Chromium did not dissolve during LTAD. (7) Chloride concentration increased in the liquid phase during LTAD due to chloride contamination in the 50% sodium hydroxide solution. (8) The rate of heat loss from Tank 51 at temperatures above 45 C appeared linear and predictable at 8E+7 cal/hr. (9) The rate of heat transfer from Tank 51 did not follow a simplified bulk heat transfer model. (10) Prediction of the aluminum dissolution rate was prone to error due to a lack of active specific surface area data of sludge particles. (11) The higher than expected dissolution rate during LTAD was likely due to smaller than expected particle sizes of most of the sludge particles. While evaluating the LTAD process, the dissolved salt solution from

  8. Solution Processing of Cadmium Sulfide Buffer Layer and Aluminum-Doped Zinc Oxide Window Layer for Thin Films Solar Cells

    NASA Astrophysics Data System (ADS)

    Alam, Mahboob; Islam, Mohammad; Achour, Amine; Hayat, Ansar; Ahsan, Bilal; Rasheed, Haroon; Salam, Shahzad; Mujahid, Mohammad

    2014-07-01

    Cadmium sulfide (CdS) and aluminum-doped zinc oxide (Al:ZnO) thin films are used as buffer layer and front window layer, respectively, in thin film solar cells. CdS and Al:ZnO thin films were produced using chemical bath deposition (CBD) and sol-gel technique, respectively. For CBD CdS, the effect of bath composition and temperature, dipping time and annealing temperature on film properties was investigated. The CdS films are found to be polycrystalline with metastable cubic crystal structure, dense, crack-free surface morphology and the crystallite size of either few nanometers or 12-17 nm depending on bath composition. In case of CdS films produced with 1:2 ratio of Cd and S precursors, spectrophotometer studies indicate quantum confinement effect, owing to extremely small crystallite size, with an increase in Eg value from 2.42 eV (for bulk CdS) to 3.76 eV along with a shift in the absorption edge toward 330 nm wavelength. The optimum annealing temperature is 400°C beyond which film properties deteriorate through S evaporation and CdO formation. On the other hand, Al:ZnO films prepared via spin coating of precursor sols containing 0.90-1.10 at.% Al show that, with an increase in Al concentration, the average grain size increases from 28 nm to 131 nm with an associated decrease in root-mean-square roughness. The minimum value of electrical resistivity, measured for the films prepared using 0.95 at.% Al in the precursor sol, is 2.7 × 10-4 Ω ṡ cm. The electrical resistivity value rises upon further increase in Al doping level due to introduction of lattice defects and Al segregation to the grain boundary area, thus limiting electron transport through it.

  9. Recycling of aluminum salt cake

    SciTech Connect

    Jody, B.J.; Daniels, E.J.; Bonsignore, P.V.; Karvelas, D.E.

    1991-12-01

    The secondary aluminum industry generates more than 110 {times} 10{sup 3} tons of salt-cake waste every year. This waste stream contains about 3--5% aluminum, 15--30% aluminum oxide, 30--40% sodium chloride, and 20--30% potassium chloride. As much as 50% of the content of this waste is combined salt (sodium and potassium chlorides). Salt-cake waste is currently disposed of in conventional landfills. In addition, over 50 {times} 10{sup 3} tons of black dross that is not economical to reprocess a rotary furnace for aluminum recovery ends up in landfills. The composition of the dross is similar to that of salt cake, except that it contains higher concentrations of aluminum (up to 20%) and correspondingly lower amounts of salts. Because of the high solubility of the salts in water, these residues, when put in landfills, represent a potential source of pollution to surface-water and groundwater supplies. The increasing number of environmental regulations on the generation and disposal of industrial wastes are likely to restrict the disposal of these salt-containing wastes in conventional landfills. Processes exist that employ the dissolution and recovery of the salts from the waste stream. These wet-processing methods are economical only when the aluminum concentration in that waste exceeds about 10%. Argonne National Laboratory (ANL) conducted a study in which existing technologies were reviewed and new concepts that are potentially more cost-effective than existing processes were developed and evaluated. These include freeze crystallization, solvent/antisolvent extraction, common-ion effect, high-pressure/high-temperature process, and capillary-effect systems. This paper presents some of the technical and economic results of the aforementioned ANL study.

  10. Copper, aluminum, iron and calcium inhibit human acetylcholinesterase in vitro.

    PubMed

    Pohanka, Miroslav

    2014-01-01

    Acetylcholinesterase (AChE) is an important part of cholinergic nerves where it participates in termination of neurotransmission. AChE can be inhibited by e.g. some Alzheimer disease drugs, nerve agents, and secondary metabolites. In this work, metal salts aluminum chloride, calcium chloride, cupric chloride, ferric chloride, potassium chloride, magnesium chloride and sodium chloride were tested for their ability to inhibit AChE. Standard Ellman assay based on human recombinant AChE was done and inhibition was measured using Dixon plot. No inhibition was proved for sodium, potassium and magnesium ions. However, aluminum, cupric, ferric and calcium ions were able to inhibit AChE via noncompetitive mechanism of inhibition. Though the inhibition is much weaker when compared to e.g. drugs with noncompetitive mechanism of action, biological relevance of the findings can be anticipated. PMID:24473150

  11. Habit changes of lead chloride, PbCl 2, caused by growth from pure aqueous solution and the effect of KCl, NH 4Cl, CdCl 2 and HCl as additives

    NASA Astrophysics Data System (ADS)

    Van Panhuys-Sigler, M.; Hartman, P.; Woensdregt, C. F.

    1988-03-01

    Crystallization of lead chloride, PbCl 2, from pure aqueous solution produces crystals with dominant {211} and smaller {010} and {100} faces at low supersaturation. Increase of supersaturation yields crystals elongated along the c axis. Growth from a previously prepared saturated solution gives crystals elongated along the c axis with {011} as main terminal faces. This habit also occurs when KCl, NH 4Cl or CdCl 2 or mixtures of these are added to a freshly prepared supersaturated solution. Only at low additive concentration and at low supersaturation {211} is dominant. The latter habit is supposed to be caused by adsorption of OH - ions on {211}. A deposit of Pb(OH)Cl has been observed. Crystallization from HCl containing solutions enhances the {010} and {121} forms, presumably through preferred adsorption of H + and possibly PbCl -3 ions. Increasing supersaturation diminishes the effect of the habit modifying process until the stage where dendrites appear.

  12. Extracting aluminum from dross tailings

    NASA Astrophysics Data System (ADS)

    Amer, A. M.

    2002-11-01

    Aluminum dross tailings, an industrial waste, from the Egyptian Aluminium Company (Egyptalum) was used to produce two types of alums: aluminum-sulfate alum [itAl2(SO4)3.12H2O] and ammonium-aluminum alum [ (NH 4)2SO4AL2(SO4)3.24H2O]. This was carried out in two processes. The first process is leaching the impurities using diluted H2SO4 with different solid/liquid ratios at different temperatures to dissolve the impurities present in the starting material in the form of solute sulfates. The second process is the extraction of aluminum (as aluminum sulfate) from the purifi ed aluminum dross tailings thus produced. The effects of temperature, time of reaction, and acid concentration on leaching and extraction processes were studied. The product alums were analyzed using x-ray diffraction and thermal analysis techniques.

  13. Dissolution and Separation of Aluminum and Aluminosilicates

    DOE PAGESBeta

    McFarlane, Joanna; Benker, Dennis; DePaoli, David W.; Felker, Leslie Kevin; Mattus, Catherine H.

    2015-12-19

    The selection of an aluminum alloy for target irradiation affects post-irradiation target dissolution and separations. Recent tests with aluminum alloy 6061 yielded greater than expected precipitation in the dissolver, forming up to 10 wt.% solids of aluminum hydroxides and aluminosilicates. Aluminosilicate dissolution presents challenges in a number of different areas, metals extraction from minerals, flyash treatment, and separations from aluminum alloys. We present experimental work that attempts to maximize dissolution of aluminum metal, along with silicon, magnesium, and copper impurities, through control of temperature, the rate of reagent addition, and incubation time. Aluminum phase transformations have been identified as amore » function of time and temperature, using X-ray diffraction. Solutions have been analyzed using wet chemical methods and X-ray fluorescence. Our data have been compared with published calculations of aluminum phase diagrams. Approaches are given to enhance the dissolution of aluminum and aluminosilicate phases in caustic solution.« less

  14. Dissolution and Separation of Aluminum and Aluminosilicates

    SciTech Connect

    McFarlane, Joanna; Benker, Dennis; DePaoli, David W.; Felker, Leslie Kevin; Mattus, Catherine H.

    2015-12-19

    The selection of an aluminum alloy for target irradiation affects post-irradiation target dissolution and separations. Recent tests with aluminum alloy 6061 yielded greater than expected precipitation in the dissolver, forming up to 10 wt.% solids of aluminum hydroxides and aluminosilicates. Aluminosilicate dissolution presents challenges in a number of different areas, metals extraction from minerals, flyash treatment, and separations from aluminum alloys. We present experimental work that attempts to maximize dissolution of aluminum metal, along with silicon, magnesium, and copper impurities, through control of temperature, the rate of reagent addition, and incubation time. Aluminum phase transformations have been identified as a function of time and temperature, using X-ray diffraction. Solutions have been analyzed using wet chemical methods and X-ray fluorescence. Our data have been compared with published calculations of aluminum phase diagrams. Approaches are given to enhance the dissolution of aluminum and aluminosilicate phases in caustic solution.

  15. Molecular dynamics simulation study of ionic hydration and ion association in dilute and 1 molal aqueous sodium chloride solutions from ambient to supercritical conditions

    NASA Astrophysics Data System (ADS)

    Driesner, T.; Seward, T. M.; Tironi, I. G.

    1998-09-01

    The increasing demand for accurate equations of state of fluids under extreme conditions and the need for a detailed microscopic picture of aqueous fluids in some areas of geochemistry (e.g., mineral dissolution/precipitation kinetics) potentially make molecular dynamics (MD) simulations a powerful tool for theoretical geochemistry. We present MD simulations of infinitely dilute and 1 molal aqueous NaCl solutions that have been carried out in order to study the systematics of hydration and ion association over a wide range of conditions from ambient to supercritical and compare them to the available experimental data. In the dilute case, the hydration number of the Na + ion remains essentially constant around 5.5 from ambient to supercritical temperatures when the density is kept constant at 1 g cm -3 but decreases to below 5 along the liquid-vapor curve. In both cases, the average ion-first shell water distance decreases by about 0.03 Å from ambient to near critical temperatures. The Cl - ion shows a slight expansion of the first hydration shell by about 0.02 Å from ambient to near critical temperatures. The geometric definition of the first hydration shell becomes ambiguous due to a shift of the position of the first minimum of the Cl-O radial distribution function. In the case of the 1 molal solution, the contraction of the Na + first hydration shell is similar to that in the dilute case whereas the hydration number decreases drastically from 4.9 to 2.8 due to strong ion association. The released waters are replaced on a near 1:1 basis by chloride ions. Polynuclear clusters as predicted by Oelkers and Helgeson (1993b) are observed in the high temperature systems. The hydration shell of the Cl --ion shows significant deviation from the behavior in dilute systems, that is, at near vapor saturated conditions, the expansion of the hydration shell is significantly larger (0.12 Å from ambient to near critical temperatures). Due to a very large shift of the first

  16. Electrochemical generation of aluminum sorbent for fluoride adsorption.

    PubMed

    Yang, Chen-Yu; Dluhy, Robert

    2002-10-14

    Aluminum sorbent (Al-sorbent) was produced in a parallel-plate electrochemical reactor by anodic dissolution of aluminum electrodes in a dilute sodium chloride (NaCl) aqueous solution. The NaCl in the solution effectively reduced the power consumption and promoted the sorbent generation by depasivating the aluminum-water electrochemical system. The freshly generated Al-sorbent was able to reduce fluoride concentration from 16 to 2 mg/l in 2 min. The final concentration was further reduced to 0.1 mg/l by partial neutralization of the mixture to pH 6.3. The sorbent generation and fluoride adsorption was integrated into a single electrochemical reactor. The system was able to reduce the fluoride concentration from 16 to 6 mg/l in 2 min of treatment and to about 2 mg/l in 4 min. The effluent from the electrochemical system needs pH adjustment to bring the fluoride concentration down to less than 1 mg/l. PMID:12220827

  17. REMOVAL OF ALUMINUM COATINGS

    DOEpatents

    Peterson, J.H.

    1959-08-25

    A process is presented for dissolving aluminum jackets from uranium fuel elements without attack of the uranium in a boiling nitric acid-mercuric nitrate solution containing up to 50% by weight of nitrtc acid and mercuric nitrate in a concentration of between 0.05 and 1% by weight.

  18. Aqueous recovery of actinides from aluminum alloys

    SciTech Connect

    Gray, J.H.; Chostner, D.F.; Gray, L.W.

    1989-01-01

    Early in the 1980's, a joint Rocky Flats/Savannah River program was established to recover actinides from scraps and residues generated during Rocky Flats purification operations. The initial program involved pyrochemical treatment of Molten Salt Extraction (MSE) chloride salts and Electrorefining (ER) anode heel metal to form aluminum alloys suitable for aqueous processing at Savannah River. Recently Rocky Flats has expressed interest in expanding the aluminum alloy program to include treatment of chloride salt residues from a modified Molten Salt Extraction process and from the Electrorefining purification operations. Samples of the current aluminum alloy buttons were prepared at Rocky Flats and sent to Savannah River Laboratory for flowsheet development and characterization of the alloys. A summary of the scrub alloy-anode heel alloy program will be presented along with recent results from aqueous dissolution studies of the new aluminum alloys. 2 figs., 4 tabs.

  19. Pigment-derived inhibitors for aluminum alloy 2024-T3

    SciTech Connect

    Cook, R.L. Jr.; Taylor, S.R.

    2000-03-01

    Inhibitor characteristics of 27 compounds considered as possible replacements for chromate pigments in aerospace paint were investigated. These compounds were tested and screened in solution and not as actual paint additives. In initial testing, aluminum alloy (AA) 2024-T3 (UNS A92024) samples were exposed to 0.6 M sodium chloride (NaCl, pH adjusted to 7, T = 23 C) with 3.4 mM of the candidate compound dissolved in solution. Corrosion inhibition characteristics were assessed via electrochemical impedance spectroscopy (EIS) performed over 10 days, and the statistical analysis of pit depths was analyzed at the conclusion of each exposure. Promising candidates then were exposed to more extreme environments to simulate possible service-life conditions. These environments included unbuffered 0.6 M NaCl initially adjusted to pH 3, T = 23 C and pH 10, T = 23 C. Several candidate inhibitors appeared promising: barium metaborate, cerium chloride, cerium oxalate, lanthanum chloride, and sodium metavanadate. Under the conditions of these tests, sodium metavanadate consistently displayed the best performance. EIS data indicated the corrosion performance of sodium metavanadata was within an order of magnitude of sodium chromate (Na{sub 2}CrO{sub 4}), while pit depth values for metavanadate were comparable to those observed for Na{sub 2}CrO{sub 4}. Rankings of inhibitor performance as determined by EIS was supported by the extreme value analysis of pit depth.

  20. Al/sub 2/S/sub 3/ preparation and use in electrolysis process for aluminum production

    DOEpatents

    Hsu, C.C.; Loutfy, R.O.; Yao, N.P.

    A continuous process for producing aluminum sulfide and for electrolyzing the aluminum sulfide to form metallic aluminum in which the aluminum sulfide is produced from aluminum oxide and COS or CS/sub 2/ in the presence of a chloride melt which also serves as the electrolysis bath. Circulation between the reactor and electrolysis cell is carried out to maintain the desired concentration of aluminum sulfide in the bath.

  1. Corrosion behavior of aluminum-lithium alloys

    SciTech Connect

    Garrard, W.N. )

    1994-03-01

    Corrosion behavior of three aluminum-lithium (Al-Li) alloys was investigated in aerated 0.5 M sodium sulfate (Na[sub 2]SO[sub 4]), deaerated 3.5% sodium chloride (NaCl), and aerated 3.5% NaCl. Corrosion behavior of the Aluminum Association (AA) alloys 2090-T8E41 (UNS A92090, sheet), AA 8090-T851 (UNS A98090, sheet), and AA 8090-T82551 (UNS A98090, bar) was compared to behavior of the conventional AA 7075-T6 (UNS A97075, sheet). Uniform corrosion was the predominant form of attack in aerated Na[sub 2]SO[sub 4] and deaerated NaCl, although some localized attack resulted from corrosion of intermetallics on specimen surfaces. Pitting was the main form of attack in aerated NaCl. In all three media, the sheet materials corroded at a similar rate, but the bar form of AA 8090 corroded at a lower rate. Pretreatment of the alloys by immersion in a cerium (Ce) solution inhibited pitting in aerated NaCl but only for a short period.

  2. pH-Dependent retention changes during membrane filtration of aluminum-coagulated solutions and the effect of precentrifugation.

    PubMed

    Bérubé, Denis; Dorea, Caetano

    2013-03-19

    During jar tests on alum-based drinking water treatment, dissolved Al determinations on solutions coagulated at pH ≥ 6.5 were not reproducible. These determinations were performed by inductively coupled plasma mass spectrometry after syringe filtration (0.45 μm polyethersulfone membrane). In order to better define these anomalies, the filtrates were collected in sequential fractions of 7.5 mL. At coagulation pHs of 6.5 and 7.0, retention changes were demonstrated by large filtrate concentration reductions at all temperatures tested (0.1, 5.0, and 17.0 °C). In all cases, the concentrations converged to levels <50 μg/L within the fourth sequential fraction. In comparison, no retention change was observed for jar tests conducted at the same temperatures but in the low range of the minimum solubility domain, at pHs 5.5 and 6.0. The retention changes were also eliminated by precentrifugation (7000 g for 45 min; pH 6.5-7.2). At weaker precentrifugation conditions, as well as by varying membrane surface area or membrane fouling, the filtrate concentrations behaved according to a barrier buildup at the membrane-solution interface by unsettled flocculation residuals. The influence of flocculation time and temperature emphasized the importance of reaction rates, which could be enhanced at the interface by concentration polarization effects. These phenomena have implications on analytical protocols and on filtration in full-scale treatment. PMID:23413878

  3. Iron-aluminum alloys having high room-temperature and method for making same

    DOEpatents

    Sikka, V.K.; McKamey, C.G.

    1993-08-24

    A wrought and annealed iron-aluminum alloy is described consisting essentially of 8 to 9.5% aluminum, an effective amount of chromium sufficient to promote resistance to aqueous corrosion of the alloy, and an alloying constituent selected from the group of elements consisting of an effective amount of molybdenum sufficient to promote solution hardening of the alloy and resistance of the alloy to pitting when exposed to solutions containing chloride, up to about 0.05% carbon with up to about 0.5% of a carbide former which combines with the carbon to form carbides for controlling grain growth at elevated temperatures, and mixtures thereof, and the balance iron, wherein said alloy has a single disordered [alpha] phase crystal structure, is substantially non-susceptible to hydrogen embrittlement, and has a room-temperature ductility of greater than 20%.

  4. Galvanic corrosion of aluminum-matrix composites. Technical report No. 2, 1 Mar-31 Dec 90

    SciTech Connect

    Hihara, L.H.; Latanision, R.M.

    1991-02-01

    Galvanic-corrosion rates of Al-matrix composites were high in aerated chloride-containing solutions. Oxygen reduction was found to be the primary cathodic reaction. Aluminum corroded by pitting. The type of noble constituent (i.e., graphite, SiC, or TiB{sub 2}) also affected galvanic-corrosion rates. For example, results indicated that the galvanic-corrosion rate of Al should be about 30 times greater when coupled to graphite than when coupled to SiC or TiB{sub 2}. In dearated solutions, galvanic corrosion was negligible even if chlorides were present. The galvanic-corrosion rates were determined using the zero-resistance ammeter technique and from potentiodynamic polarization diagrams of ultrapure Al, 6061-T6 Al, graphite fiber, SiC, TiB2, and a commercial graphite fiber/6061-T6 Al metal-matrix composite.

  5. Influence of anodization parameters on the volume expansion of anodic aluminum oxide formed in mixed solution of phosphoric and oxalic acids

    NASA Astrophysics Data System (ADS)

    Kao, Tzung-Ta; Chang, Yao-Chung

    2014-01-01

    The growth of anodic alumina oxide was conducted in the mixed solution of phosphoric and oxalic acids. The influence of anodizing voltage, electrolyte temperature, and concentration of phosphoric and oxalic acids on the volume expansion of anodic aluminum oxide has been investigated. Either anodizing parameter is chosen to its full extent of range that allows the anodization process to be conducted without electric breakdown and to explore the highest possible volume expansion factor. The volume expansion factors were found to vary between 1.25 and 1.9 depending on the anodizing parameters. The variation is explained in connection with electric field, ion transport number, temperature effect, concentration, and activity of acids. The formation of anodic porous alumina at anodizing voltage 160 V in 1.1 M phosphoric acid mixed with 0.14 M oxalic acid at 2 °C showed the peak volume expansion factor of 1.9 and the corresponding moderate growth rate of 168 nm/min.

  6. Solution structure of oxidized rat microsomal cytochrome b5 in the presence of 2 M guanidinium chloride: monitoring the early steps in protein unfolding.

    PubMed

    Arnesano, F; Banci, L; Bertini, I; Koulougliotis, D

    1998-12-01

    One- and two-dimensional proton NMR spectroscopy has been employed in order to study the denaturation effect of guanidinium chloride (GdmCl) on the oxidized state of the A-form of rat microsomal cytochrome b5 (cyt b5). The protein rapidly starts losing the heme at denaturant concentrations larger than approximately 2.0 M and a largely unfolded protein is eventually obtained. An estimate of the unfolding kinetics is obtained and, by use of a two-state model (folded left and right arrow unfolded), a value for DeltaG degrees. Below this concentration, small (solution structure of the protein in the presence of 2 M GdmCl. By use of 1199 meaningful NOESY constraints (obtained from the assignment of 75% of the total protons) and 166 pseudocontact shifts, a family of 40 structures has been obtained through the program PSEUDYANA. The family was further refined through restrained energy minimization and the final root mean square deviation (RMSD) values with respect to the average structure are 0.67 +/- 0.10 A and 1.14 +/- 0.11 A for the backbone and heavy atoms, respectively. The quality of the present structure is equivalent to that of the one obtained recently for the native form [Arnesano et al. (1998) Biochemistry 37, 173-184], thus allowing a meaningful comparison between the two structures. Upon addition of 2 M GdmCl, significant local structural differences are induced to the protein backbone segments comprising residues 33-38 (helix alpha2) and 62-64 (end of helix alpha4-beginning of helix alpha5) while the overall folding scheme of the protein is still maintained. These protein regions form part of the "pocket

  7. Dehydration of highly concentrated solutions of fructose to 5-hydroxymethylfurfural in a cheap and sustainable choline chloride/carbon dioxide system.

    PubMed

    Liu, Fei; Barrault, Joël; De Oliveira Vigier, Karine; Jérôme, François

    2012-07-01

    Fête DES sciences: The dehydration of fructose and inulin to HMF is conveniently performed in a cheap and sustainable choline chloride/CO(2) deep eutectic solvent (DES) system. The medium is capable of converting high contents of fructose (>100 wt %) without affecting the yield of HMF (up to 72 %). The purity of the recovered HMF is >98%, and the reaction medium can be recycled. PMID:22644952

  8. Study of crevice-galvanic corrosion of aluminum

    NASA Technical Reports Server (NTRS)

    Draley, J. E.; Loess, R. E.; Mori, S.

    1967-01-01

    Corrosion effects of aluminum-copper and aluminum-nickel couples in oxygenated distilled water, and aluminum alloys in oxygenated copper sulfate solution were studied. One of each of the couples had a water tight seal, and showed no substantial corrosion, and of the unsealed couples, only the aluminum-copper developed corrosion.

  9. Aluminum Analysis.

    ERIC Educational Resources Information Center

    Sumrall, William J.

    1998-01-01

    Presents three problems based on the price of aluminum designed to encourage students to be cooperative and to use an investigative approach to learning. Students collect and synthesize information, analyze results, and draw conclusions. (AIM)

  10. Aluminum Hydroxide

    MedlinePlus

    ... penicillamine (Cuprimine, Depen), prednisone (Deltasone, Orasone), products containing iron, tetracycline (Sumycin, Tetracap, and others), ticlopidine (Ticlid), and vitamins.be aware that aluminum hydroxide may interfere with other medicines, making them less effective. Take your other medications 1 ...

  11. Advances in the electrodeposition of aluminum from ionic liquid based electrolytes

    NASA Astrophysics Data System (ADS)

    Leadbetter, Kirt C.

    Aluminum plating is of considerable technical and economic interest because it provides an eco-friendly substitute for cadmium coatings used on many military systems. However, cadmium has been determined to be a significant environmental safety and occupational health (ESOH) hazard because of its toxicity and carcinogenic nature. Furthermore, the cost of treating and disposing of generated wastes, which often contain cyanide, is costly and is becoming prohibitive in the face of increasingly stringent regulatory standards. The non-toxic alternative aluminum is equivalent or superior in performance to cadmium. In addition, it could serve to provide an alternative to hexavalent chromium coatings used on military systems for similar reasons to that of cadmium. Aluminum is a beneficial alternative in that it demonstrates self-healing corrosion resistance in the form of a tightly-bound, impervious oxide layer. A successfully plated layer would be serviceable over a wider temperature range, 925 °F for aluminum compared to 450 oF for cadmium. In addition, an aluminum layer can be anodized to make it non-conducting and colorable. In consideration of the plating process, aluminum cannot be deposited from aqueous solutions because of its reduction potential. Therefore, nonaqueous electrolytes are required for deposition. Currently, aluminum can be electrodeposited in nonaqueous processes that use hazardous chemicals such as toluene and pyrophoric aluminum alkyls. Electrodeposition from ionic liquids provides the potential for a safer method that could be easily scaled up for industrial application. The plating process could be performed at a lower temperature and higher current density than other commercially available aluminum electrodeposition processes; thus a reduced process cost could be possible. The current ionic liquid based electrolytes are more expensive; however production on a larger scale and a long electrolyte lifetime are associated with a reduction in price

  12. New biodegradable amphiphilic block copolymers of epsilon-caprolactone and delta-valerolactone catalyzed by novel aluminum metal complexes. II. Micellization and solution to gel transition.

    PubMed

    Yang, Jing; Jia, Lin; Hao, Qinghui; Li, Yang; Li, Qiaobo; Fang, Qiang; Cao, Amin

    2005-09-16

    In our previous study [J. Yang, L. Jia, L. Yin, J. Yu, Z. Shi, Q. Fang, A. Cao, Macromol. Biosci. 2004, 4, 1092.], new biodegradable copolymers of diblock methoxy poly(ethylene glycol)-block-poly(epsilon-caprolactone) and methoxy poly(ethylene glycol)-block-poly(delta-valerolactone), and triblock poly(epsilon-caprolactone)-block-poly(ethylene glycol)-block-poly(epsilon-caprolactone) and poly(delta-valerolactone)-block-poly(ethylene glycol)-block-poly(delta-valero-lactone) bearing narrow molecular weight distributions and well-defined block architectures were reported to be prepared with our original aluminum metal complex templates. This work will continue to report new investigations on their water solubility, and reversible thermal responsive micellization and solution to gel transition in distilled water. Among the new synthesized copolymers (P1-P23), seven diblock or triblock samples (P3, P6, P7, P11, P12, P19, and P21) with higher hydrophilic building block populations were revealed to be water soluble under ambient temperature. By means of UV spectrophotometer attached with a thermostat, important parameters as critical micellization mass concentrations (CMCs) and critical micellization temperatures (CMTs) were characterized for these new amphiphile dilute aqueous solution with the aid of an lipophilic organic dye probe of 1,6-diphenyl-1,3,5-hexatriene (DPH). Furthermore, the critical gelation temperatures (CGTs) were simultaneously investigated for these water-soluble block copolymers via a tube tilting method. It was found that the CMC, CMT, and CGT were strongly affected by the population and nature of the hydrophobic building blocks, and a higher hydrophobicity of the new amphiphilic block copolymer finally led to lower CMC and CMT, and higher CGT. In addition, the salts of KBr and NaCl were found to play as a salt-out effect on the solution to gel transition for the diblock P6 and triblock P11, exhibiting an interesting tunable gelation temperature close

  13. Stability of succinylcholine chloride injection.

    PubMed

    Schmutz, C W; Mühlebach, S F

    1991-03-01

    The stability of succinylcholine chloride injection prepared by a hospital pharmacy was studied under a wide variety of conditions. Batches of succinylcholine chloride injection 10 mg/mL containing sodium chloride, methyl-4-hydroxybenzoate, hydrochloric acid, and water were prepared. Samples were tested for the effect of initial pH (3.0 and 4.2) and sterilization (steam treatment at 100 degrees C for 30 minutes and 121 degrees C for 20 minutes) on stability after three weeks; long-term stability under refrigeration (12, 17, and 23 months of storage at 4 degrees C); and the effect of storage temperature (4-6 degrees C, 20-26 degrees C, 35 degrees C, and 70 degrees C) and light exposure at various intervals up to 12 months. Samples were analyzed by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Unlike heating at 121 degrees C, heating at 100 degrees C produced no significant loss of succinylcholine chloride, independent of the initial pH. Succinylcholine chloride was hydrolyzed only minimally over 23 months if the solution was stored at 4-6 degrees C. A 10% loss of drug content occurred if solutions were kept at 20-26 degrees C for five months, at 35 degrees C for one month, or at 70 degrees C for one day. Initial degradation was slowed if the solution was protected from light. The assessments by TLC proved to be more sensitive than the HPLC measurements. Succinylcholine chloride injection sterilized at 100 degrees C for 30 minutes can be stored for up to five months at room temperature if protected from light. The preparation is stable for at least two years under refrigeration. PMID:2028996

  14. An alternate to chromate conversion coatings for the corrosion protection of aluminum 2024-T3

    NASA Astrophysics Data System (ADS)

    Guo, Ruiguang

    Corrosion of high-strength aluminum alloys used for airspace application is an expensive and serious problem. The most significant environmental factor contributing to the corrosion of these alloys is water condensed from humid air and contaminated with soluble chloride salts. The Al 2024 series used for aircraft are particularly susceptible to corrosion in aqueous chloride solutions due to alloying constituents such as copper and other impurities. Chromates are efficient inhibitors of corrosion of aluminum in near neutral aqueous environments containing aggressive anions such as chlorides. Usually, aluminum alloys are initially protected by chromate conversion coatings. Additional polymer coatings are sometimes added during exposure to corrosive atmospheres such as marine environments. Although chromate coatings are widely used, they require the use of noxious solutions, so they have always presented effluent disposal problems. There are health and safety concerns over the use of chromates due to their toxicity and carcinogenic nature and, as a consequence, the environmental and health risks associated with the use of such coatings will be restricted in the future. It was these health and safety concerns that led to the development of alternative non-toxic coating processes with comparable adhesion properties and corrosion protection. A variety of process technologies are under development and are vying for acceptance in industrial markets. As an alternate conversion coating, a new titanate conversion coating was systematically researched and developed. Research concentrated on producing passive surfaces from a simple titanate solution using an immersion process. The corrosion resistance of the treated surface has been evaluated using simple, rapid electrochemical techniques as well as a more long-term salt spray test. Passivation by titanate conversion treatment exhibits many similarities to chromate conversion treatment. Based on this study of corrosion

  15. [The corrosion resistance of aluminum and aluminum-based alloys studied in artificial model media].

    PubMed

    Zhakhangirov, A Zh; Doĭnikov, A I; Aboev, V G; Iankovskaia, T A; Karamnova, V S; Sharipov, S M

    1991-01-01

    Samples of aluminum and its alloys, designed for orthodontic employment, were exposed to 4 media simulating the properties of biologic media. The corrosion resistance of the tested alloys was assessed from the degree of aluminum migration to simulation media solutions, which was measured by the neutron activation technique. Aluminum alloy with magnesium and titanium has shown the best corrosion resistance. PMID:1799002

  16. Naringin protects memory impairment and mitochondrial oxidative damage against aluminum-induced neurotoxicity in rats.

    PubMed

    Prakash, Atish; Shur, Bhargabi; Kumar, Anil

    2013-09-01

    Aluminum has been indicated in neurodegenerative disorders and naringin, a bioflavonoid has been used to reduce neurotoxic effects of aluminum against aluminum chloride-induced rats. Therefore, present study has been designed to explore the possible role of naringin against aluminum-induced cognitive dysfunction and oxidative damage in rats. Aluminum (100 mg/kg) and naringin (40 and 80 mg/kg) drug treatment were administered orally for six weeks to male wistar rats. Various behavioral performance tasks, biochemical, mitochondrial oxidative parameters, and aluminum concentration in the brain were assessed. Aluminum chloride treatment significantly caused cognitive dysfunction and mitochondria oxidative damage as compared to vehicle treated control group. Besides, aluminum chloride treatment significantly increased acetyl cholinesterase activity and aluminum concentration in the brain as compared to sham. Chronic administration of naringin significantly improved cognitive performance and attenuated mitochondria oxidative damage, acetyl cholinesterase activity, and aluminum concentration in aluminum-treated rats as compared to control rats. Results of the study demonstrate neuroprotective potential of naringin against aluminum chloride-induced cognitive dysfunction and mitochondrial oxidative damage. PMID:23510099

  17. Stress Corrosion Cracking Behavior of Multipass TIG-Welded AA2219 Aluminum Alloy in 3.5 wt pct NaCl Solution

    NASA Astrophysics Data System (ADS)

    Venugopal, A.; Sreekumar, K.; Raja, V. S.

    2012-09-01

    The stress corrosion cracking (SCC) behavior of the AA2219 aluminum alloy in the single-pass (SP) and multipass (MP) welded conditions was examined and compared with that of the base metal (BM) in 3.5 wt pct NaCl solution using a slow-strain-rate technique (SSRT). The reduction in ductility was used as a parameter to evaluate the SCC susceptibility of both the BM and welded joints. The results showed that the ductility ratio ( ɛ NaCl/( ɛ air) was 0.97 and 0.96, respectively, for the BM and MP welded joint, and the same was marginally reduced to 0.9 for the SP welded joint. The fractographic examination of the failed samples revealed a typical ductile cracking morphology for all the base and welded joints, indicating the good environmental cracking resistance of this alloy under all welded conditions. To understand the decrease in the ductility of the SP welded joint, preexposure SSRT followed by microstructural observations were made, which showed that the decrease in ductility ratio of the SP welded joint was caused by the electrochemical pitting that assisted the nucleation of cracks in the form of corrosion induced mechanical cracking rather than true SCC failure of the alloy. The microstructural examination and polarization tests demonstrated a clear grain boundary (GB) sensitization of the PMZ, resulting in severe galvanic corrosion of the SP weld joint, which initiated the necessary conditions for the localized corrosion and cracking along the PMZ. The absence of PMZ and a refined fusion zone (FZ) structure because of the lesser heat input and postweld heating effect improved the galvanic corrosion resistance of the MP welded joint greatly, and thus, failure occurred along the FZ.

  18. Recovery of aluminum from composite propellants

    NASA Technical Reports Server (NTRS)

    Shaw, G. C. (Inventor)

    1980-01-01

    Aluminum was recovered from solid rocket propellant containing a small amount of oxidizer by depolymerizing and dissolving propellant binders (containing functional or hydrolyzable groups in a solution of sodium methoxide) in an alcohol solvent optionally containing an aliphatic or aromatic hydrocarbon co-solvent. The solution was filtered to recover substantially all the aluminum in active form.

  19. Making Positive Electrodes For Sodium/Metal Chloride Cells

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V.; Distefano, Salvador; Bankston, C. Perry

    1992-01-01

    High coulombic yields provided by sodium/metal chloride battery in which cathode formed by impregnating sintered nickel plaque with saturated solution of nickel chloride. Charge/discharge cycling of nickel chloride electrode results in very little loss of capacity. Used in spacecraft, electric land vehicles, and other applications in which high-energy-density power systems required.

  20. Effect of sodium chloride on glassy and crystalline transitions of wheat starch treated with high hydrostatic pressure: Prediction of solute-induced barostability from nonmonotonic solute-induced thermostability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat starch was high hydrostatic pressure (HHP)-treated in various sodium chloride (NaCl) concentrations (0 to near-saturation), in order to explore the effects of salt on glassy and crystalline transitions of starch during the treatment, using differential scanning calorimetry (DSC). For wheat st...

  1. Polymer gel electrolytes for application in aluminum deposition and rechargeable aluminum ion batteries

    SciTech Connect

    Sun, Xiao -Guang; Fang, Youxing; Jiang, Xueguang; Yoshii, Kazuki; Tsuda, Tetsuya; Dai, Sheng

    2015-10-22

    Polymer gel electrolyte using AlCl3 complexed acrylamide as functional monomer and ionic liquids based on acidic mixture of 1-ethyl-3-methylimidazolium chloride (EMImCl) and AlCl3 as plasticizer has been successfully prepared for the first time by free radical polymerization. Aluminum deposition is successfully obtained with a polymer gel membrane contianing 80 wt% ionic liquid. As a result, the polymer gel membranes are also good candidates for rechargeable aluminum ion batteries.

  2. Polymer gel electrolytes for application in aluminum deposition and rechargeable aluminum ion batteries

    DOE PAGESBeta

    Sun, Xiao -Guang; Fang, Youxing; Jiang, Xueguang; Yoshii, Kazuki; Tsuda, Tetsuya; Dai, Sheng

    2015-10-22

    Polymer gel electrolyte using AlCl3 complexed acrylamide as functional monomer and ionic liquids based on acidic mixture of 1-ethyl-3-methylimidazolium chloride (EMImCl) and AlCl3 as plasticizer has been successfully prepared for the first time by free radical polymerization. Aluminum deposition is successfully obtained with a polymer gel membrane contianing 80 wt% ionic liquid. As a result, the polymer gel membranes are also good candidates for rechargeable aluminum ion batteries.

  3. Alloy solution hardening with solute pairs

    DOEpatents

    Mitchell, John W.

    1976-08-24

    Solution hardened alloys are formed by using at least two solutes which form associated solute pairs in the solvent metal lattice. Copper containing equal atomic percentages of aluminum and palladium is an example.

  4. Aluminum alloy

    NASA Technical Reports Server (NTRS)

    Blackburn, Linda B. (Inventor); Starke, Edgar A., Jr. (Inventor)

    1989-01-01

    This invention relates to aluminum alloys, particularly to aluminum-copper-lithium alloys containing at least about 0.1 percent by weight of indium as an essential component, which are suitable for applications in aircraft and aerospace vehicles. At least about 0.1 percent by weight of indium is added as an essential component to an alloy which precipitates a T1 phase (Al2CuLi). This addition enhances the nucleation of the precipitate T1 phase, producing a microstructure which provides excellent strength as indicated by Rockwell hardness values and confirmed by standard tensile tests.

  5. Aluminum permanganate battery

    SciTech Connect

    Marsh, C.; Licht, S.L.

    1993-11-30

    A battery is provided comprising an aluminum anode, an aqueous solution of permanganate as the cathodic species and a second electrode capable of reducing permanganate. Such a battery system is characterized by its high energy density and low polarization losses when operating at high temperatures in a strong caustic electrolyte, i.e., high concentration of hydroxyl ions. A variety of anode and electrocatalyst materials are suitable for the efficient oxidation-reduction process and are elucidated.

  6. Comparison of the crevice corrosion resistance of Alloys 625 and 22 in concentrated chloride solution from 60 to 95 degrees C

    SciTech Connect

    Kehler, B A; Illevbare, G O; Scully, J R

    1999-12-06

    The effects of electrolyte composition and oxide film age on the crevice corrosion properties of alloys 625 and 22 were studied at temperatures ranging from 60 to 95 C in concentrated chloride electrolytes. Critical potentials were determined using conventional current density thresholds and comparisons were made between 625 and 22 on the basis of these critical potentials. Air aged 22 specimens exhibited the highest resistance to crevice corrosion at 95 C in terms of critical crevice potentials, while freshly polished 22 exhibited the lowest resistance. Studies over the entire, temperature range showed that air aged 22 is more resistant to crevice corrosion than air aged 625 as evidenced by higher critical crevice potentials. As the temperature was lowered from 95 to 8O C, critical crevice potentials for 22 either approached or exceeded experimentally determined Cr (Mo, Ni) transpassive potentials.

  7. Production of sodium-22 from proton irradiated aluminum

    DOEpatents

    Taylor, Wayne A.; Heaton, Richard C.; Jamriska, David J.

    1996-01-01

    A process for selective separation of sodium-22 from a proton irradiated minum target including dissolving a proton irradiated aluminum target in hydrochloric acid to form a first solution including aluminum ions and sodium ions, separating a portion of the aluminum ions from the first solution by crystallization of an aluminum salt, contacting the remaining first solution with an anion exchange resin whereby ions selected from the group consisting of iron and copper are selectively absorbed by the anion exchange resin while aluminum ions and sodium ions remain in solution, contacting the solution with an cation exchange resin whereby aluminum ions and sodium ions are adsorbed by the cation exchange resin, and, contacting the cation exchange resin with an acid solution capable of selectively separating the adsorbed sodium ions from the cation exchange resin while aluminum ions remain adsorbed on the cation exchange resin is disclosed.

  8. Thermodynamic properties of aqueous-alcoholic solutions of sodium chloride. H2O-2-C3H7OH-NaCl

    NASA Astrophysics Data System (ADS)

    Veryaeva, E. S.; Konstantinova, N. M.; Mamontov, M. N.; Uspenskaya, I. A.

    2010-11-01

    The temperature-concentration dependences of the NaCl activity coefficient in aqueous solutions of isopropanol (propanol-2) at temperatures of 298.15 and 323.15 K (solution ionic force, 0.01 to 3 m; alcohol content, 10-60 wt %) were determined through the electromotive force method with an ion-selective electrode. A Pitzer model was used to mathematically describe the thermodynamic properties. The integral Gibbs energy of the solution formation of the H2O-2-C3H7OH-NaCl ternary system was performed according to Darken's method. The dissociation degree of salt in the investigated solutions was estimated using the literature data on the association constant of NaCl in aqueous-isopropanol solution.

  9. Shelf life of unrefrigerated succinylcholine chloride injection.

    PubMed

    Boehm, J J; Dutton, D M; Poust, R I

    1984-02-01

    The shelf life of succinylcholine chloride injection at several pH values when stored at room temperature was evaluated. Solutions containing 20 mg/ml of succinylcholine chloride were stored at 25 and 40 degrees C. The reaction was studied at pH values ranging from 3.0 to 4.5. At two-week intervals, the solutions were assayed by high-pressure liquid chromatography. The initial amount of succinylcholine chloride in all samples was 100.1 +/- 2.37% of label claim. Hydrolysis of succinylcholine chloride in unbuffered solutions followed apparent zero-order kinetics. The pH range of maximum stability was found to be from 3.75 to 4.50. Succinylcholine chloride decomposed at a considerably higher rate at 40 degrees C. Allowing for the effects of pH adjustment during manufacture and degradation during shipping, losses of 7.0% and 9.0% potency can be expected after storage at 25 degrees C for four and six weeks, respectively. Succinylcholine Chloride Injection, USP, should be stored in the refrigerator; if unbuffered succinylcholine chloride injection complying with USP pH limits must be stored at room temperature, it should not be kept for longer than four weeks. PMID:6702837

  10. Chloride in diet

    MedlinePlus

    ... found in table salt or sea salt as sodium chloride. It is also found in many vegetables. Foods ... Nutrition Board. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. National Academy Press, Washington, DC: 2005. ...

  11. Aluminum phosphide

    Integrated Risk Information System (IRIS)

    Aluminum phosphide ; CASRN 20859 - 73 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  12. 4 f-4 f hypersensitivity in the absorption spectra and NMR studies on paramagnetic lanthanide chloride complexes with 1,10-phenanthroline in non-aqueous solutions

    NASA Astrophysics Data System (ADS)

    Hussain, H. A.; Iftikhar, K.

    2003-03-01

    The optical absorption and NMR studies of trivalent lanthanide chloride complexes with 1,10-phenanthroline (phen) are presented and discussed. The 1H NMR spectra of the complexes of La, Pr, Nd, Eu and Yb have been studied in methanol- d4. The resonances of phen in the NMR spectra of the paramagnetic complexes have been shifted to lower as well as higher fields, which is a manifestation of dipolar interaction. The H (2) protons of the heterocyclic amine display broad resonances. The degree of broadening in Pr, Nd, and Yb complexes follows the order Pr

  13. Mesoporous aluminum phosphite

    SciTech Connect

    El Haskouri, Jamal; Perez-Cabero, Monica; Guillem, Carmen; Latorre, Julio; Beltran, Aurelio; Beltran, Daniel; Amoros, Pedro

    2009-08-15

    High surface area pure mesoporous aluminum-phosphorus oxide-based derivatives have been synthesized through an S{sup +}I{sup -} surfactant-assisted cooperative mechanism by means of a one-pot preparative procedure from aqueous solution and starting from aluminum atrane complexes and phosphoric and/or phosphorous acids. A soft chemical extraction procedure allows opening the pore system of the parent as-prepared materials by exchanging the surfactant without mesostructure collapse. The nature of the pore wall can be modulated from mesoporous aluminum phosphate (ALPO) up to total incorporation of phosphite entities (mesoporous aluminum phosphite), which results in a gradual evolution of the acidic properties of the final materials. While phosphate groups in ALPO act as network building blocks (bridging Al atoms), the phosphite entities become basically attached to the pore surface, what gives practically empty channels. The mesoporous nature of the final materials is confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and N{sub 2} adsorption-desorption isotherms. The materials present regular unimodal pore systems whose order decreases as the phosphite content increases. NMR spectroscopic results confirm the incorporation of oxo-phosphorus entities to the framework of these materials and also provide us useful information concerning the mechanism through which they are formed. - Abstract: TEM image of the mesoporous aluminum phosphite showing the hexagonal disordered pore array that is generated by using surfactant micelles as template. Also a scheme emphasizing the presence of an alumina-rich core and an ALPO-like pore surface is presented.

  14. Advanced intermediate temperature sodium copper chloride battery

    NASA Astrophysics Data System (ADS)

    Yang, Li-Ping; Liu, Xiao-Min; Zhang, Yi-Wei; Yang, Hui; Shen, Xiao-Dong

    2014-12-01

    Sodium metal chloride batteries, also called as ZEBRA batteries, possess many merits such as low cost, high energy density and high safety, but their high operation temperature (270-350 °C) may cause several issues and limit their applications. Therefore, decreasing the operation temperature is of great importance in order to broaden their usage. Using a room temperature ionic liquid (RTIL) catholyte composed of sodium chloride buffered 1-ethyl-3-methylimidazolium chloride-aluminum chloride and a dense β″-aluminates solid electrolyte film with 500 micron thickness, we report an intermediate temperature sodium copper chloride battery which can be operated at only 150 °C, therefore alleviating the corrosion issues, improving the material compatibilities and reducing the operating complexities associated with the conventional ZEBRA batteries. The RTIL presents a high ionic conductivity (0.247 S cm-1) at 150 °C and a wide electrochemical window (-2.6 to 2.18 vs. Al3+/Al). With the discharge plateau at 2.64 V toward sodium and the specific capacity of 285 mAh g-1, this intermediate temperature battery exhibits an energy density (750 mWh g-1) comparable to the conventional ZEBRA batteries (728-785 mWh g-1) and superior to commercialized Li-ion batteries (550-680 mWh g-1), making it very attractive for renewable energy integration and other grid related applications.

  15. Determination of the heat capacities of Lithium/BCX (bromide chloride in thionyl chloride) batteries

    NASA Technical Reports Server (NTRS)

    Kubow, Stephen A.; Takeuchi, Kenneth J.; Takeuchi, Esther S.

    1989-01-01

    Heat capacities of twelve different Lithium/BCX (BrCl in thionyl chloride) batteries in sizes AA, C, D, and DD were determined. Procedures and measurement results are reported. The procedure allowed simple, reproducible, and precise determinations of heat capacities of industrially important Lithium/BCX cells, without interfering with performance of the cells. Use of aluminum standards allowed the accuracy of the measurements to be maintained. The measured heat capacities were within 5 percent of calculated heat capacity values.

  16. Investigation of acute nanoparticulate aluminum toxicity in zebrafish.

    PubMed

    Griffitt, Robert J; Feswick, April; Weil, Roxana; Hyndman, Kelly; Carpinone, Paul; Powers, Kevin; Denslow, Nancy D; Barber, David S

    2011-10-01

    In freshwater fish, aluminum is a well-recognized gill toxicant, although responses are influenced by pH. Aluminum nanomaterials are being used in diverse applications that are likely to lead to environmental release and exposure. However, it is unclear if the effects of nanoparticulate aluminum are similar to those of other forms of aluminum or require special consideration. To examine the acute toxicological effects of exposure to aluminum nanoparticle (Al-NP)s, adult female zebrafish were exposed to either Al-NPs or aluminum chloride for up to 48 hours in moderately hard fresh water. Al-NPs introduced into test water rapidly aggregated and up to 80% sedimented from the water column during exposures. No mortality was caused by concentrations of Al-NP up to 12.5 mg/L. After exposure, tissue concentrations of aluminum, effects on gill morphology, Na+, K+ -ATPase (NKA) activity, and global gene expression patterns were examined. Exposure to both aluminum chloride and nanoparticulate aluminum resulted in a concentration dependent decrease in sodium potassium ATPase activity, although Al-NP exposure did not alter gill morphology as measured by filament widths. Decreased ATPase activity coincided with decreases in filamental NKA staining and mucous cell counts. Analysis of gill transcriptional responses demonstrated that exposure to 5 mg/L Al-NP only resulted in significant changes in expression of two genes, whereas aluminum chloride exposure significantly affected the expression of 105 genes. Taken together, these results indicate that nanoparticulate aluminum has little acute toxicity for zebrafish in moderately hard freshwater. PMID:21910207

  17. Diluting ferric carboxymaltose in sodium chloride infusion solution (0.9% w/v) in polypropylene bottles and bags: effects on chemical stability

    PubMed Central

    Philipp, Erik; Braitsch, Michaela; Bichsel, Tobias; Mühlebach, Stefan

    2016-01-01

    Objectives This study was designed to assess the physicochemical stability of colloidal ferric carboxymaltose solution (Ferinject) when diluted and stored in polypropylene (PP) bottles and bags for infusion. Methods Two batches of ferric carboxymaltose solution (Ferinject) were diluted (500 mg, 200 mg and 100 mg iron in 100 mL saline) in PP bottles or bags under aseptic conditions. The diluted solutions were stored at 30°C and 75%±5% relative humidity (rH) for 72 h, and samples were withdrawn aseptically at preparation and after 24 h, 48 h and 72 h. Multiple parameters were used to test stability-related measures (pH, total iron and iron (II) content, molecular weight range determination, microbial contamination and particles count ≥10 μm). Results Overall, Ferinject diluted in 0.9% (w/v) NaCl solution and stored in PP bottles and bags was stable within the specifications for the complex and the acceptability limits set for all assays. In both containers, total iron content remained stable, within 10% of the theoretical iron content, and levels of iron (II) remained far below the threshold of acceptability. All preparations were free from sediments, particle numbers were acceptable and there was no microbial contamination. The molecular weight distribution and polydispersity index were also acceptable. Conclusions Under the tested experimental conditions, colloidal ferric carboxymaltose solution (Ferinject) diluted in saline in PP infusion bottles or bags demonstrated physical and chemical stability for up to 72 h at 30°C and 75% rH. Because of the lack of additional clinical data, when using ferric carboxymaltose, physicians/pharmacists should refer to the dilution and storing recommendations given in the product's summary of product characteristics. PMID:26835007

  18. Chloride Ion Activity and Susceptibility of Al Alloys 7075-T6 and 5083-H131 to Stress Corrosion Cracking

    NASA Astrophysics Data System (ADS)

    Ricker, R. E.; Lee, E. U.; Taylor, R.; Lei, C.; Pregger, B.; Lipnickas, E.

    2013-03-01

    The influence of chloride ion activity on the susceptibility of aluminum alloys 5083-H131 and 7075-T6 to stress corrosion cracking (SCC) was investigated by conducting slow strain-rate tensile tests at a strain-rate of 10-7 s-1 in naturally aerated aqueous solutions with varying NaCl mass fraction (0.001 to 20 pct) and in a 3.5 pct mass fraction NaCl solution with varying strain-rates (10-8 to 10-4 s-1). This study found that both alloys exhibited reduced strengths and failure strains (times) in the solutions compared with laboratory air. The extent of these reductions was greater in alloy 5083 for the conditions examined. The strength and ductility of both alloys decreased with chloride ion activity in a manner that indicates a chemical reaction is responsible. The strength and ductility of both alloys decreased with strain-rate in a sigmoidal manner, but the transition in alloy 7075 occurred at slower strain-rates of approximately two orders of magnitude. It was deduced that the chloride ion interacts chemically with the passivated surface in the potential gradient at the crack tip to cause SCC. While no mechanism of cracking can be eliminated on the basis of these results alone, the results are consistent with the hypothesis that the absorbed hydrogen causes cracking in alloy 7075 while cracking in 5083 is the result of a dissolution mechanism.

  19. Aluminum induced proteome changes in tomato cotyledons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotyledons of tomato seedlings that germinated in a 20 µM AlK(SO4)2 solution remained chlorotic while those germinated in an aluminum free medium were normal (green) in color. Previously, we have reported the effect of aluminum toxicity on root proteome in tomato seedlings (Zhou et al. J Exp Bot, 20...

  20. Abnormal passive chloride absorption in cystic fibrosis jejunum functionally opposes the classic chloride secretory defect

    PubMed Central

    Russo, Michael A.; Högenauer, Christoph; Coates, Stephen W.; Santa Ana, Carol A.; Porter, Jack L.; Rosenblatt, Randall L.; Emmett, Michael; Fordtran, John S.

    2003-01-01

    Due to genetic defects in apical membrane chloride channels, the cystic fibrosis (CF) intestine does not secrete chloride normally. Depressed chloride secretion leaves CF intestinal absorptive processes unopposed, which results in net fluid hyperabsorption, dehydration of intestinal contents, and a propensity to inspissated intestinal obstruction. This theory is based primarily on in vitro studies of jejunal mucosa. To determine if CF patients actually hyperabsorb fluid in vivo, we measured electrolyte and water absorption during steady-state perfusion of the jejunum. As expected, chloride secretion was abnormally low in CF, but surprisingly, there was no net hyperabsorption of sodium or water during perfusion of a balanced electrolyte solution. This suggested that fluid absorption processes are reduced in CF jejunum, and further studies revealed that this was due to a marked depression of passive chloride absorption. Although Na+-glucose cotransport was normal in the CF jejunum, absence of passive chloride absorption completely blocked glucose-stimulated net sodium absorption and reduced glucose-stimulated water absorption 66%. This chloride absorptive abnormality acts in physiological opposition to the classic chloride secretory defect in the CF intestine. By increasing the fluidity of intraluminal contents, absence of passive chloride absorption may reduce the incidence and severity of intestinal disease in patients with CF. PMID:12840066